diff --git a/src/triacontagon/data.py b/src/triacontagon/data.py
new file mode 100644
index 0000000..4505adf
--- /dev/null
+++ b/src/triacontagon/data.py
@@ -0,0 +1,209 @@
+#
+# Copyright (C) Stanislaw Adaszewski, 2020
+# License: GPLv3
+#
+
+
+from collections import defaultdict
+from dataclasses import dataclass, field
+import torch
+from typing import List, \
+    Dict, \
+    Tuple, \
+    Any, \
+    Type
+from .decode import DEDICOMDecoder, \
+    BilinearDecoder
+import numpy as np
+
+
+def _equal(x: torch.Tensor, y: torch.Tensor):
+    if x.is_sparse ^ y.is_sparse:
+        raise ValueError('Cannot mix sparse and dense tensors')
+
+    if not x.is_sparse:
+        return (x == y)
+
+    return ((x - y).coalesce().values() == 0)
+
+
+@dataclass
+class NodeType(object):
+    name: str
+    count: int
+
+
+@dataclass
+class RelationTypeBase(object):
+    name: str
+    node_type_row: int
+    node_type_column: int
+    adjacency_matrix: torch.Tensor
+    adjacency_matrix_backward: torch.Tensor
+
+
+@dataclass
+class RelationType(RelationTypeBase):
+    pass
+
+
+@dataclass
+class RelationFamilyBase(object):
+    data: 'Data'
+    name: str
+    node_type_row: int
+    node_type_column: int
+    is_symmetric: bool
+    decoder_class: Type
+
+
+@dataclass
+class RelationFamily(RelationFamilyBase):
+    relation_types: List[RelationType] = None
+
+    def __post_init__(self) -> None:
+        if not self.is_symmetric and \
+            self.decoder_class != DEDICOMDecoder and \
+            self.decoder_class != BilinearDecoder:
+            raise TypeError('Family is assymetric but the specified decoder_class supports symmetric relations only')
+
+        self.relation_types = []
+
+    def add_relation_type(self,
+        name: str, adjacency_matrix: torch.Tensor,
+        adjacency_matrix_backward: torch.Tensor = None) -> None:
+
+        name = str(name)
+        node_type_row = self.node_type_row
+        node_type_column = self.node_type_column
+
+        if adjacency_matrix is None and adjacency_matrix_backward is None:
+            raise ValueError('adjacency_matrix and adjacency_matrix_backward cannot both be None')
+
+        if adjacency_matrix is not None and \
+            not isinstance(adjacency_matrix, torch.Tensor):
+            raise ValueError('adjacency_matrix must be a torch.Tensor')
+
+        if adjacency_matrix_backward is not None \
+            and not isinstance(adjacency_matrix_backward, torch.Tensor):
+            raise ValueError('adjacency_matrix_backward must be a torch.Tensor')
+
+        if adjacency_matrix is not None and \
+            adjacency_matrix.shape != (self.data.node_types[node_type_row].count,
+                self.data.node_types[node_type_column].count):
+            raise ValueError('adjacency_matrix shape must be (num_row_nodes, num_column_nodes)')
+
+        if adjacency_matrix_backward is not None and \
+            adjacency_matrix_backward.shape != (self.data.node_types[node_type_column].count,
+                self.data.node_types[node_type_row].count):
+            raise ValueError('adjacency_matrix_backward shape must be (num_column_nodes, num_row_nodes)')
+
+        if node_type_row == node_type_column and \
+            adjacency_matrix_backward is not None:
+            raise ValueError('Relation between nodes of the same type must be expressed using a single matrix')
+
+        if self.is_symmetric and adjacency_matrix_backward is not None:
+            raise ValueError('Cannot use a custom adjacency_matrix_backward in a symmetric relation family')
+
+        if self.is_symmetric and node_type_row == node_type_column and \
+            not torch.all(_equal(adjacency_matrix,
+                adjacency_matrix.transpose(0, 1))):
+            raise ValueError('Relation family is symmetric but adjacency_matrix is assymetric')
+
+        if not self.is_symmetric and node_type_row != node_type_column and \
+            adjacency_matrix_backward is None:
+            raise ValueError('Relation is asymmetric but adjacency_matrix_backward is None')
+
+        if self.is_symmetric and node_type_row != node_type_column:
+            adjacency_matrix_backward = adjacency_matrix.transpose(0, 1)
+
+        self.relation_types.append(RelationType(name,
+            node_type_row, node_type_column,
+            adjacency_matrix, adjacency_matrix_backward))
+
+    def node_name(self, index):
+        return self.data.node_types[index].name
+
+    def __repr__(self):
+        s = 'Relation family %s' % self.name
+
+        for r in self.relation_types:
+            s += '\n  - %s%s' % (r.name, ' (two-way)' \
+                if (r.adjacency_matrix is not None \
+                    and r.adjacency_matrix_backward is not None) \
+                        or self.node_type_row == self.node_type_column \
+                            else '%s <- %s' % (self.node_name(self.node_type_row),
+                                self.node_name(self.node_type_column)))
+
+        return s
+
+    def repr_indented(self):
+        s = '  - %s' % self.name
+
+        for r in self.relation_types:
+            s += '\n    - %s%s' % (r.name, ' (two-way)' \
+                if (r.adjacency_matrix is not None \
+                    and r.adjacency_matrix_backward is not None) \
+                        or self.node_type_row == self.node_type_column \
+                            else '%s <- %s' % (self.node_name(self.node_type_row),
+                                self.node_name(self.node_type_column)))
+
+        return s
+
+
+class Data(object):
+    node_types: List[NodeType]
+    relation_families: List[RelationFamily]
+
+    def __init__(self) -> None:
+        self.node_types = []
+        self.relation_families = []
+
+    def add_node_type(self, name: str, count: int) -> None:
+        name = str(name)
+        count = int(count)
+        if not name:
+            raise ValueError('You must provide a non-empty node type name')
+        if count <= 0:
+            raise ValueError('You must provide a positive node count')
+        self.node_types.append(NodeType(name, count))
+
+    def add_relation_family(self, name: str, node_type_row: int,
+        node_type_column: int, is_symmetric: bool,
+        decoder_class: Type = DEDICOMDecoder):
+
+        name = str(name)
+        node_type_row = int(node_type_row)
+        node_type_column = int(node_type_column)
+        is_symmetric = bool(is_symmetric)
+
+        if node_type_row < 0 or node_type_row >= len(self.node_types):
+            raise ValueError('node_type_row outside of the valid range of node types')
+
+        if node_type_column < 0 or node_type_column >= len(self.node_types):
+            raise ValueError('node_type_column outside of the valid range of node types')
+
+        fam = RelationFamily(self, name, node_type_row, node_type_column,
+            is_symmetric, decoder_class)
+        self.relation_families.append(fam)
+
+        return fam
+
+    def __repr__(self):
+        n = len(self.node_types)
+        if n == 0:
+            return 'Empty Icosagon Data'
+        s = ''
+        s += 'Icosagon Data with:\n'
+        s += '- ' + str(n) + ' node type(s):\n'
+        for nt in self.node_types:
+            s += '  - ' + nt.name + '\n'
+        if len(self.relation_families) == 0:
+            s += '- No relation families\n'
+            return s.strip()
+
+        s += '- %d relation families:\n' % len(self.relation_families)
+        for fam in self.relation_families:
+            s += fam.repr_indented() + '\n'
+
+        return s.strip()
diff --git a/src/triacontagon/decode.py b/src/triacontagon/decode.py
new file mode 100644
index 0000000..00df8b2
--- /dev/null
+++ b/src/triacontagon/decode.py
@@ -0,0 +1,123 @@
+#
+# Copyright (C) Stanislaw Adaszewski, 2020
+# License: GPLv3
+#
+
+
+import torch
+from .weights import init_glorot
+from .dropout import dropout
+
+
+class DEDICOMDecoder(torch.nn.Module):
+    """DEDICOM Tensor Factorization Decoder model layer for link prediction."""
+    def __init__(self, input_dim, num_relation_types, keep_prob=1.,
+        activation=torch.sigmoid, **kwargs):
+
+        super().__init__(**kwargs)
+        self.input_dim = input_dim
+        self.num_relation_types = num_relation_types
+        self.keep_prob = keep_prob
+        self.activation = activation
+
+        self.global_interaction = torch.nn.Parameter(init_glorot(input_dim, input_dim))
+        self.local_variation = torch.nn.ParameterList([
+            torch.nn.Parameter(torch.flatten(init_glorot(input_dim, 1))) \
+                for _ in range(num_relation_types)
+        ])
+
+    def forward(self, inputs_row, inputs_col, relation_index):
+        inputs_row = dropout(inputs_row, self.keep_prob)
+        inputs_col = dropout(inputs_col, self.keep_prob)
+
+        relation = torch.diag(self.local_variation[relation_index])
+
+        product1 = torch.mm(inputs_row, relation)
+        product2 = torch.mm(product1, self.global_interaction)
+        product3 = torch.mm(product2, relation)
+        rec = torch.bmm(product3.view(product3.shape[0], 1, product3.shape[1]),
+            inputs_col.view(inputs_col.shape[0], inputs_col.shape[1], 1))
+        rec = torch.flatten(rec)
+
+        return self.activation(rec)
+
+
+class DistMultDecoder(torch.nn.Module):
+    """DEDICOM Tensor Factorization Decoder model layer for link prediction."""
+    def __init__(self, input_dim, num_relation_types, keep_prob=1.,
+        activation=torch.sigmoid, **kwargs):
+
+        super().__init__(**kwargs)
+        self.input_dim = input_dim
+        self.num_relation_types = num_relation_types
+        self.keep_prob = keep_prob
+        self.activation = activation
+
+        self.relation = torch.nn.ParameterList([
+            torch.nn.Parameter(torch.flatten(init_glorot(input_dim, 1))) \
+                for _ in range(num_relation_types)
+        ])
+
+    def forward(self, inputs_row, inputs_col, relation_index):
+        inputs_row = dropout(inputs_row, self.keep_prob)
+        inputs_col = dropout(inputs_col, self.keep_prob)
+
+        relation = torch.diag(self.relation[relation_index])
+
+        intermediate_product = torch.mm(inputs_row, relation)
+        rec = torch.bmm(intermediate_product.view(intermediate_product.shape[0], 1, intermediate_product.shape[1]),
+            inputs_col.view(inputs_col.shape[0], inputs_col.shape[1], 1))
+        rec = torch.flatten(rec)
+
+        return self.activation(rec)
+
+
+class BilinearDecoder(torch.nn.Module):
+    """DEDICOM Tensor Factorization Decoder model layer for link prediction."""
+    def __init__(self, input_dim, num_relation_types, keep_prob=1.,
+        activation=torch.sigmoid, **kwargs):
+
+        super().__init__(**kwargs)
+        self.input_dim = input_dim
+        self.num_relation_types = num_relation_types
+        self.keep_prob = keep_prob
+        self.activation = activation
+
+        self.relation = torch.nn.ParameterList([
+            torch.nn.Parameter(init_glorot(input_dim, input_dim)) \
+                for _ in range(num_relation_types)
+        ])
+
+    def forward(self, inputs_row, inputs_col, relation_index):
+        inputs_row = dropout(inputs_row, self.keep_prob)
+        inputs_col = dropout(inputs_col, self.keep_prob)
+
+        intermediate_product = torch.mm(inputs_row, self.relation[relation_index])
+        rec = torch.bmm(intermediate_product.view(intermediate_product.shape[0], 1, intermediate_product.shape[1]),
+            inputs_col.view(inputs_col.shape[0], inputs_col.shape[1], 1))
+        rec = torch.flatten(rec)
+
+        return self.activation(rec)
+
+
+class InnerProductDecoder(torch.nn.Module):
+    """DEDICOM Tensor Factorization Decoder model layer for link prediction."""
+    def __init__(self, input_dim, num_relation_types, keep_prob=1.,
+        activation=torch.sigmoid, **kwargs):
+
+        super().__init__(**kwargs)
+        self.input_dim = input_dim
+        self.num_relation_types = num_relation_types
+        self.keep_prob = keep_prob
+        self.activation = activation
+
+
+    def forward(self, inputs_row, inputs_col, _):
+        inputs_row = dropout(inputs_row, self.keep_prob)
+        inputs_col = dropout(inputs_col, self.keep_prob)
+
+        rec = torch.bmm(inputs_row.view(inputs_row.shape[0], 1, inputs_row.shape[1]),
+            inputs_col.view(inputs_col.shape[0], inputs_col.shape[1], 1))
+        rec = torch.flatten(rec)
+
+        return self.activation(rec)
diff --git a/src/triacontagon/dropout.py b/src/triacontagon/dropout.py
new file mode 100644
index 0000000..63cfb58
--- /dev/null
+++ b/src/triacontagon/dropout.py
@@ -0,0 +1,42 @@
+#
+# Copyright (C) Stanislaw Adaszewski, 2020
+# License: GPLv3
+#
+
+
+import torch
+from .normalize import _sparse_coo_tensor
+
+
+def dropout_sparse(x, keep_prob):
+    x = x.coalesce()
+    i = x._indices()
+    v = x._values()
+    size = x.size()
+
+    n = keep_prob + torch.rand(len(v))
+    n = torch.floor(n).to(torch.bool)
+    i = i[:,n]
+    v = v[n]
+    x = _sparse_coo_tensor(i, v, size=size)
+
+    return x * (1./keep_prob)
+
+
+def dropout_dense(x, keep_prob):
+    # print('dropout_dense()')
+    x = x.clone()
+    i = torch.nonzero(x)
+
+    n = keep_prob + torch.rand(len(i))
+    n = (1. - torch.floor(n)).to(torch.bool)
+    x[i[n, 0], i[n, 1]] = 0.
+
+    return x * (1./keep_prob)
+
+
+def dropout(x, keep_prob):
+    if x.is_sparse:
+        return dropout_sparse(x, keep_prob)
+    else:
+        return dropout_dense(x, keep_prob)
diff --git a/src/triacontagon/fastconv.py b/src/triacontagon/fastconv.py
new file mode 100644
index 0000000..038e2fc
--- /dev/null
+++ b/src/triacontagon/fastconv.py
@@ -0,0 +1,255 @@
+from typing import List, \
+    Union, \
+    Callable
+from .data import Data, \
+    RelationFamily
+from .trainprep import PreparedData, \
+    PreparedRelationFamily
+import torch
+from .weights import init_glorot
+from .normalize import _sparse_coo_tensor
+import types
+
+
+def _sparse_diag_cat(matrices: List[torch.Tensor]):
+    if len(matrices) == 0:
+        raise ValueError('The list of matrices must be non-empty')
+
+    if not all(m.is_sparse for m in matrices):
+        raise ValueError('All matrices must be sparse')
+
+    if not all(len(m.shape) == 2 for m in matrices):
+        raise ValueError('All matrices must be 2D')
+
+    indices = []
+    values = []
+    row_offset = 0
+    col_offset = 0
+
+    for m in matrices:
+        ind = m._indices().clone()
+        ind[0] += row_offset
+        ind[1] += col_offset
+        indices.append(ind)
+        values.append(m._values())
+        row_offset += m.shape[0]
+        col_offset += m.shape[1]
+
+    indices = torch.cat(indices, dim=1)
+    values = torch.cat(values)
+
+    return _sparse_coo_tensor(indices, values, size=(row_offset, col_offset))
+
+
+def _cat(matrices: List[torch.Tensor]):
+    if len(matrices) == 0:
+        raise ValueError('Empty list passed to _cat()')
+
+    n = sum(a.is_sparse for a in matrices)
+    if n != 0 and n != len(matrices):
+        raise ValueError('All matrices must have the same layout (dense or sparse)')
+
+    if not all(a.shape[1:] == matrices[0].shape[1:] for a in matrices):
+        raise ValueError('All matrices must have the same dimensions apart from dimension 0')
+
+    if not matrices[0].is_sparse:
+        return torch.cat(matrices)
+
+    total_rows = sum(a.shape[0] for a in matrices)
+    indices = []
+    values = []
+    row_offset = 0
+
+    for a in matrices:
+        ind = a._indices().clone()
+        val = a._values()
+        ind[0] += row_offset
+        ind = ind.transpose(0, 1)
+        indices.append(ind)
+        values.append(val)
+        row_offset += a.shape[0]
+
+    indices = torch.cat(indices).transpose(0, 1)
+    values = torch.cat(values)
+
+    res = _sparse_coo_tensor(indices, values, size=(row_offset, matrices[0].shape[1]))
+    return res
+
+
+class FastGraphConv(torch.nn.Module):
+    def __init__(self,
+        in_channels: int,
+        out_channels: int,
+        adjacency_matrices: List[torch.Tensor],
+        keep_prob: float = 1.,
+        activation: Callable[[torch.Tensor], torch.Tensor] = lambda x: x,
+        **kwargs) -> None:
+
+        super().__init__(**kwargs)
+
+        in_channels = int(in_channels)
+        out_channels = int(out_channels)
+        if not isinstance(adjacency_matrices, list):
+            raise TypeError('adjacency_matrices must be a list')
+        if len(adjacency_matrices) == 0:
+            raise ValueError('adjacency_matrices must not be empty')
+        if not all(isinstance(m, torch.Tensor) for m in adjacency_matrices):
+            raise TypeError('adjacency_matrices elements must be of class torch.Tensor')
+        if not all(m.is_sparse for m in adjacency_matrices):
+            raise ValueError('adjacency_matrices elements must be sparse')
+        keep_prob = float(keep_prob)
+        if not isinstance(activation, types.FunctionType):
+            raise TypeError('activation must be a function')
+
+        self.in_channels = in_channels
+        self.out_channels = out_channels
+        self.adjacency_matrices = adjacency_matrices
+        self.keep_prob = keep_prob
+        self.activation = activation
+
+        self.num_row_nodes = len(adjacency_matrices[0])
+        self.num_relation_types = len(adjacency_matrices)
+
+        self.adjacency_matrices = _sparse_diag_cat(adjacency_matrices)
+
+        self.weights = torch.cat([
+            init_glorot(in_channels, out_channels) \
+            for _ in range(self.num_relation_types)
+        ], dim=1)
+
+    def forward(self, x) -> torch.Tensor:
+        if self.keep_prob < 1.:
+            x = dropout(x, self.keep_prob)
+        res = torch.sparse.mm(x, self.weights) \
+            if x.is_sparse \
+            else torch.mm(x, self.weights)
+        res = torch.split(res, res.shape[1] // self.num_relation_types, dim=1)
+        res = torch.cat(res)
+        res = torch.sparse.mm(self.adjacency_matrices, res) \
+            if self.adjacency_matrices.is_sparse \
+            else torch.mm(self.adjacency_matrices, res)
+        res = res.view(self.num_relation_types, self.num_row_nodes, self.out_channels)
+        if self.activation is not None:
+            res = self.activation(res)
+
+        return res
+
+
+class FastConvLayer(torch.nn.Module):
+    def __init__(self,
+        input_dim: List[int],
+        output_dim: List[int],
+        data: Union[Data, PreparedData],
+        keep_prob: float = 1.,
+        rel_activation: Callable[[torch.Tensor], torch.Tensor] = lambda x: x,
+        layer_activation: Callable[[torch.Tensor], torch.Tensor] = torch.nn.functional.relu,
+        **kwargs):
+
+        super().__init__(**kwargs)
+
+        self._check_params(input_dim, output_dim, data, keep_prob,
+            rel_activation, layer_activation)
+
+        self.input_dim = input_dim
+        self.output_dim = output_dim
+        self.data = data
+        self.keep_prob = keep_prob
+        self.rel_activation = rel_activation
+        self.layer_activation = layer_activation
+
+        self.is_sparse = False
+        self.next_layer_repr = None
+        self.build()
+
+    def build(self):
+        self.next_layer_repr = torch.nn.ModuleList([
+            torch.nn.ModuleList() \
+                for _ in range(len(self.data.node_types))
+        ])
+        for fam in self.data.relation_families:
+            self.build_family(fam)
+
+    def build_family(self, fam) -> None:
+        if fam.node_type_row == fam.node_type_column:
+            self.build_fam_one_node_type(fam)
+        else:
+            self.build_fam_two_node_types(fam)
+
+    def build_fam_one_node_type(self, fam) -> None:
+        adjacency_matrices = [
+            r.adjacency_matrix \
+                for r in fam.relation_types
+        ]
+        conv = FastGraphConv(self.input_dim[fam.node_type_column],
+            self.output_dim[fam.node_type_row],
+            adjacency_matrices,
+            self.keep_prob,
+            self.rel_activation)
+        conv.input_node_type = fam.node_type_column
+        self.next_layer_repr[fam.node_type_row].append(conv)
+
+    def build_fam_two_node_types(self, fam) -> None:
+        adjacency_matrices = [
+            r.adjacency_matrix \
+                for r in fam.relation_types \
+                    if r.adjacency_matrix is not None
+        ]
+
+        adjacency_matrices_backward = [
+            r.adjacency_matrix_backward \
+                for r in fam.relation_types \
+                    if r.adjacency_matrix_backward is not None
+        ]
+
+        conv = FastGraphConv(self.input_dim[fam.node_type_column],
+            self.output_dim[fam.node_type_row],
+            adjacency_matrices,
+            self.keep_prob,
+            self.rel_activation)
+
+        conv_backward = FastGraphConv(self.input_dim[fam.node_type_row],
+            self.output_dim[fam.node_type_column],
+            adjacency_matrices_backward,
+            self.keep_prob,
+            self.rel_activation)
+
+        conv.input_node_type = fam.node_type_column
+        conv_backward.input_node_type = fam.node_type_row
+
+        self.next_layer_repr[fam.node_type_row].append(conv)
+        self.next_layer_repr[fam.node_type_column].append(conv_backward)
+
+    def forward(self, prev_layer_repr):
+        next_layer_repr = [ [] \
+            for _ in range(len(self.data.node_types)) ]
+        for output_node_type in range(len(self.data.node_types)):
+            for conv in self.next_layer_repr[output_node_type]:
+                rep = conv(prev_layer_repr[conv.input_node_type])
+                rep = torch.sum(rep, dim=0)
+                rep = torch.nn.functional.normalize(rep, p=2, dim=1)
+                next_layer_repr[output_node_type].append(rep)
+            if len(next_layer_repr[output_node_type]) == 0:
+                next_layer_repr[output_node_type] = \
+                    torch.zeros(self.data.node_types[output_node_type].count, self.output_dim[output_node_type])
+            else:
+                next_layer_repr[output_node_type] = \
+                    sum(next_layer_repr[output_node_type])
+                next_layer_repr[output_node_type] = \
+                    self.layer_activation(next_layer_repr[output_node_type])
+        return next_layer_repr
+
+    @staticmethod
+    def _check_params(input_dim, output_dim, data, keep_prob,
+        rel_activation, layer_activation):
+
+        if not isinstance(input_dim, list):
+            raise ValueError('input_dim must be a list')
+
+        if not output_dim:
+            raise ValueError('output_dim must be specified')
+
+        if not isinstance(output_dim, list):
+            output_dim = [output_dim] * len(data.node_types)
+
+        if not isinstance(data, Data) and not isinstance(data, PreparedData):
+            raise ValueError('data must be of type Data or PreparedData')
diff --git a/src/triacontagon/fastdec.py b/src/triacontagon/fastdec.py
new file mode 100644
index 0000000..ca08892
--- /dev/null
+++ b/src/triacontagon/fastdec.py
@@ -0,0 +1,138 @@
+import torch
+from typing import List
+from .trainprep import PreparedData
+from dataclasses import dataclass
+import random
+from collections import defaultdict
+
+
+@dataclass
+class TrainingBatch(object):
+    relation_family_index: int
+    relation_type_index: int
+    node_type_row: int
+    node_type_column: int
+    edges: torch.Tensor
+
+
+class FastBatcher(object):
+    def __init__(self,
+        prep_d: PreparedData,
+        batch_size: int) -> None:
+
+        if not isinstance(prep_d, PreparedData):
+            raise TypeError('prep_d must be an instance of PreparedData')
+
+        self.prep_d = prep_d
+        self.batch_size = int(batch_size)
+
+        self.edges = None
+        self.build()
+
+    def build(self):
+        self.edges = []
+        for fam_idx, fam in enumerate(self.prep_d.relation_families):
+            edges = []
+            targets = []
+            edges_back = []
+            targets_back = []
+            for rel_idx, rel in enumerate(fam.relation_types):
+                edges.append(rel.edges_pos.train)
+                edges.append(rel.edges_neg.train)
+                targets.append(torch.ones(len(rel.edges_pos.train)))
+                targets.append(torch.zeros(len(rel.edges_neg.train)))
+
+                edges_back.append(rel.edges_back_pos.train)
+                edges_back.append(rel.edges_back_neg.train)
+                targets_back.apend(torch.zeros(len(rel.edges_back_pos.train)))
+                targets_back.apend(torch.zeros(len(rel.edges_back_neg.train)))
+
+            edges = torch.cat(edges)
+            targets = torch.cat(targets)
+            edges_back = torch.cat(edges_back)
+            targets_back = torch.cat(targets_back)
+
+            order = torch.randperm(len(edges))
+            edges = edges[order]
+            targets = targets[order]
+
+            order_back = torch.randperm(len(edges_back))
+            edges_back = edges_back[order_back]
+            targets_back = targets_back[order_back]
+
+            self.edges.append({'fam_idx': fam_idx, 'rel_idx': rel_idx, 'back': False,
+                'edges': edges, 'targets': targets, 'ofs': 0})
+            self.edges.append({'fam_idx': fam_idx, 'rel_idx': rel_idx, 'back': True,
+                'edges': edges_back, 'targets': targets_back, 'ofs': 0})
+
+    def __iter__(self):
+        while True:
+            edges = [ e for e in self.edges \
+                if e['ofs'] < len(e['edges']) ]
+            # TODO: need to finish this
+
+    def __iter_old__(self):
+        edge_types = ['edges_pos', 'edges_neg', 'edges_back_pos', 'edges_back_neg']
+
+        offsets = {}
+        orders = {}
+        done = {}
+
+        for fam_idx, fam in enumerate(self.prep_d.relation_families):
+            for rel_idx, rel in enumerate(fam.relation_types):
+                for et in edge_types:
+                    done[fam_idx, rel_idx, et] = False
+
+        while True:
+            fam_idx = torch.randint(0, len(self.prep_d.relation_families), (1,)).item()
+            fam = self.prep_d.relation_families[fam_idx]
+
+            rel_idx = torch.randint(0, len(fam.relation_types), (1,)).item()
+            rel = fam.relation_types[rel_idx]
+
+            et = random.choice(edge_types)
+            edges = getattr(rel, et).train
+
+            key = (fam_idx, rel_idx, et)
+            if key not in orders:
+                orders[key] = torch.randperm(len(edges))
+                offsets[key] = 0
+
+            ord = orders[key]
+            ofs = offsets[key]
+
+            nt_row = rel.node_type_row
+            nt_col = rel.node_type_column
+
+            if 'back' in et:
+                nt_row, nt_col = nt_col, nt_row
+
+            if ofs < len(edges):
+                offsets[key] += self.batch_size
+                ord = ord[ofs:ofs+self.batch_size]
+                edges = edges[ord]
+                yield TrainingBatch(fam_idx, rel_idx, nt_row, nt_column, edges)
+            else:
+                done[key] = True
+
+
+
+
+        for fam in self.prep_d.relation_families:
+            edges = []
+            for rel in fam.relation_types:
+                edges.append(rel.edges_pos.train)
+                edges.append(rel.edges_back_pos.train)
+                edges.append(rel.edges_neg.train)
+                edges.append(rel.edges_back_neg.train)
+            edges = torch.cat(e)
+
+
+
+class FastDecLayer(torch.nn.Module):
+    def __init__(self, **kwargs):
+        super().__init__(**kwargs)
+
+    def forward(self,
+        last_layer_repr: List[torch.Tensor],
+        training_batch: TrainingBatch):
diff --git a/src/triacontagon/fastloop.py b/src/triacontagon/fastloop.py
new file mode 100644
index 0000000..f955932
--- /dev/null
+++ b/src/triacontagon/fastloop.py
@@ -0,0 +1,166 @@
+from .fastmodel import FastModel
+from .trainprep import PreparedData
+import torch
+from typing import Callable
+from types import FunctionType
+import time
+import random
+
+
+class FastBatcher(object):
+    def __init__(self, prep_d: PreparedData, batch_size: int,
+        shuffle: bool, generator: torch.Generator,
+        part_type: str) -> None:
+
+        if not isinstance(prep_d, PreparedData):
+            raise TypeError('prep_d must be an instance of PreparedData')
+
+        if not isinstance(generator, torch.Generator):
+            raise TypeError('generator must be an instance of torch.Generator')
+
+        if part_type not in ['train', 'val', 'test']:
+            raise ValueError('part_type must be set to train, val or test')
+
+        self.prep_d = prep_d
+        self.batch_size = int(batch_size)
+        self.shuffle = bool(shuffle)
+        self.generator = generator
+        self.part_type = part_type
+
+        self.edges = None
+        self.targets = None
+        self.build()
+
+    def build(self):
+        self.edges = []
+        self.targets = []
+
+        for fam in self.prep_d.relation_families:
+            edges = []
+            targets = []
+            for i, rel in enumerate(fam.relation_types):
+
+                edges_pos = getattr(rel.edges_pos, self.part_type)
+                edges_neg = getattr(rel.edges_neg, self.part_type)
+                edges_back_pos = getattr(rel.edges_back_pos, self.part_type)
+                edges_back_neg = getattr(rel.edges_back_neg, self.part_type)
+
+                e = torch.cat([ edges_pos,
+                    torch.cat([edges_back_pos[:, 1], edges_back_pos[:, 0]], dim=1) ])
+                e = torch.cat([torch.ones(len(e), 1, dtype=torch.long) * i , e ], dim=1)
+                t = torch.ones(len(e))
+                edges.append(e)
+                targets.append(t)
+
+                e = torch.cat([ edges_neg,
+                    torch.cat([edges_back_neg[:, 1], edges_back_neg[:, 0]], dim=1) ])
+                e = torch.cat([ torch.ones(len(e), 1, dtype=torch.long) * i, e ], dim=1)
+                t = torch.zeros(len(e))
+                edges.append(e)
+                targets.append(t)
+
+            edges = torch.cat(edges)
+            targets = torch.cat(targets)
+
+            self.edges.append(edges)
+            self.targets.append(targets)
+
+        # print(self.edges)
+        # print(self.targets)
+
+        if self.shuffle:
+            self.shuffle_families()
+
+    def shuffle_families(self):
+        for i in range(len(self.edges)):
+            edges = self.edges[i]
+            targets = self.targets[i]
+            order = torch.randperm(len(edges), generator=self.generator)
+            self.edges[i] = edges[order]
+            self.targets[i] = targets[order]
+
+    def __iter__(self):
+        offsets = [ 0 for _ in self.edges ]
+
+        while True:
+            choice = [ i for i in range(len(offsets)) \
+                if offsets[i] < len(self.edges[i]) ]
+            if len(choice) == 0:
+                break
+            fam_idx = torch.randint(len(choice), (1,), generator=self.generator).item()
+            ofs = offsets[fam_idx]
+            edges = self.edges[fam_idx][ofs:ofs + self.batch_size]
+            targets = self.targets[fam_idx][ofs:ofs + self.batch_size]
+            offsets[fam_idx] += self.batch_size
+            yield (fam_idx, edges, targets)
+
+
+class FastLoop(object):
+    def __init__(
+        self,
+        model: FastModel,
+        lr: float = 0.001,
+        loss: Callable[[torch.Tensor, torch.Tensor], torch.Tensor] = \
+            torch.nn.functional.binary_cross_entropy_with_logits,
+        batch_size: int = 100,
+        shuffle: bool = True,
+        generator: torch.Generator = None) -> None:
+
+        self._check_params(model, loss, generator)
+
+        self.model = model
+        self.lr = float(lr)
+        self.loss = loss
+        self.batch_size = int(batch_size)
+        self.shuffle = bool(shuffle)
+        self.generator = generator or torch.default_generator
+
+        self.opt = None
+
+        self.build()
+
+    def _check_params(self, model, loss, generator):
+        if not isinstance(model, FastModel):
+            raise TypeError('model must be an instance of FastModel')
+
+        if not isinstance(loss, FunctionType):
+            raise TypeError('loss must be a function')
+
+        if generator is not None and not isinstance(generator, torch.Generator):
+            raise TypeError('generator must be an instance of torch.Generator')
+
+    def build(self) -> None:
+        opt = torch.optim.Adam(self.model.parameters(), lr=self.lr)
+        self.opt = opt
+
+    def run_epoch(self):
+        prep_d = self.model.prep_d
+
+        batcher = FastBatcher(self.model.prep_d, batch_size=self.batch_size,
+            shuffle = self.shuffle, generator=self.generator)
+        # pred = self.model(None)
+        # n = len(list(iter(batch)))
+        loss_sum = 0
+        for fam_idx, edges, targets in batcher:
+            self.opt.zero_grad()
+            pred = self.model(None)
+
+            # process pred, get input and targets
+            input = pred[fam_idx][edges[:, 0], edges[:, 1]]
+
+            loss = self.loss(input, targets)
+            loss.backward()
+            self.opt.step()
+            loss_sum += loss.detach().cpu().item()
+        return loss_sum
+
+
+    def train(self, max_epochs):
+        best_loss = None
+        best_epoch = None
+        for i in range(max_epochs):
+            loss = self.run_epoch()
+            if best_loss is None or loss < best_loss:
+                best_loss = loss
+                best_epoch = i
+        return loss, best_loss, best_epoch
diff --git a/src/triacontagon/fastmodel.py b/src/triacontagon/fastmodel.py
new file mode 100644
index 0000000..a68fe58
--- /dev/null
+++ b/src/triacontagon/fastmodel.py
@@ -0,0 +1,79 @@
+from .fastconv import FastConvLayer
+from .bulkdec import BulkDecodeLayer
+from .input import OneHotInputLayer
+from .trainprep import PreparedData
+import torch
+import types
+from typing import List, \
+    Union, \
+    Callable
+
+
+class FastModel(torch.nn.Module):
+    def __init__(self, prep_d: PreparedData,
+        layer_dimensions: List[int] = [32, 64],
+        keep_prob: float = 1.,
+        rel_activation: Callable[[torch.Tensor], torch.Tensor] = lambda x: x,
+        layer_activation: Callable[[torch.Tensor], torch.Tensor] = torch.nn.functional.relu,
+        dec_activation: Callable[[torch.Tensor], torch.Tensor] = lambda x: x,
+        **kwargs) -> None:
+
+        super().__init__(**kwargs)
+
+        self._check_params(prep_d, layer_dimensions, rel_activation,
+            layer_activation, dec_activation)
+
+        self.prep_d = prep_d
+        self.layer_dimensions = layer_dimensions
+        self.keep_prob = float(keep_prob)
+        self.rel_activation = rel_activation
+        self.layer_activation = layer_activation
+        self.dec_activation = dec_activation
+
+        self.seq = None
+        self.build()
+
+    def build(self):
+        in_layer = OneHotInputLayer(self.prep_d)
+        last_output_dim = in_layer.output_dim
+        seq = [ in_layer ]
+
+        for dim in self.layer_dimensions:
+            conv_layer = FastConvLayer(input_dim = last_output_dim,
+                output_dim = [dim] * len(self.prep_d.node_types),
+                data = self.prep_d,
+                keep_prob = self.keep_prob,
+                rel_activation = self.rel_activation,
+                layer_activation = self.layer_activation)
+            last_output_dim = conv_layer.output_dim
+            seq.append(conv_layer)
+
+        dec_layer = BulkDecodeLayer(input_dim = last_output_dim,
+            data = self.prep_d,
+            keep_prob = self.keep_prob,
+            activation = self.dec_activation)
+        seq.append(dec_layer)
+
+        seq = torch.nn.Sequential(*seq)
+        self.seq = seq
+
+    def forward(self, _):
+        return self.seq(None)
+
+    def _check_params(self, prep_d, layer_dimensions, rel_activation,
+        layer_activation, dec_activation):
+
+        if not isinstance(prep_d, PreparedData):
+            raise TypeError('prep_d must be an instanced of PreparedData')
+
+        if not isinstance(layer_dimensions, list):
+            raise TypeError('layer_dimensions must be a list')
+
+        if not isinstance(rel_activation, types.FunctionType):
+            raise TypeError('rel_activation must be a function')
+
+        if not isinstance(layer_activation, types.FunctionType):
+            raise TypeError('layer_activation must be a function')
+
+        if not isinstance(dec_activation, types.FunctionType):
+            raise TypeError('dec_activation must be a function')
diff --git a/src/triacontagon/input.py b/src/triacontagon/input.py
new file mode 100644
index 0000000..3bf5824
--- /dev/null
+++ b/src/triacontagon/input.py
@@ -0,0 +1,79 @@
+#
+# Copyright (C) Stanislaw Adaszewski, 2020
+# License: GPLv3
+#
+
+
+import torch
+from typing import Union, \
+    List
+from .data import Data
+
+
+class InputLayer(torch.nn.Module):
+    def __init__(self, data: Data, output_dim: Union[int, List[int]] = None,
+        **kwargs) -> None:
+
+        output_dim = output_dim or \
+            list(map(lambda a: a.count, data.node_types))
+
+        if not isinstance(output_dim, list):
+            output_dim = [output_dim,] * len(data.node_types)
+
+        super().__init__(**kwargs)
+        self.output_dim = output_dim
+        self.data = data
+
+        self.is_sparse=False
+        self.node_reps = None
+        self.build()
+
+    def build(self) -> None:
+        self.node_reps = []
+        for i, nt in enumerate(self.data.node_types):
+            reps = torch.rand(nt.count, self.output_dim[i])
+            reps = torch.nn.Parameter(reps)
+            self.register_parameter('node_reps[%d]' % i, reps)
+            self.node_reps.append(reps)
+
+    def forward(self, x) -> List[torch.nn.Parameter]:
+        return self.node_reps
+
+    def __repr__(self) -> str:
+        s = ''
+        s += 'Icosagon input layer with output_dim: %s\n' % self.output_dim
+        s += '  # of node types: %d\n' % len(self.data.node_types)
+        for nt in self.data.node_types:
+            s += '    - %s (%d)\n' % (nt.name, nt.count)
+        return s.strip()
+
+
+class OneHotInputLayer(torch.nn.Module):
+    def __init__(self, data: Data, **kwargs) -> None:
+        output_dim = [ a.count for a in data.node_types ]
+        super().__init__(**kwargs)
+        self.output_dim = output_dim
+        self.data = data
+
+        self.is_sparse=True
+        self.node_reps = None
+        self.build()
+
+    def build(self) -> None:
+        self.node_reps = torch.nn.ParameterList()
+        for i, nt in enumerate(self.data.node_types):
+            reps = torch.eye(nt.count).to_sparse()
+            reps = torch.nn.Parameter(reps, requires_grad=False)
+            # self.register_parameter('node_reps[%d]' % i, reps)
+            self.node_reps.append(reps)
+
+    def forward(self, x) -> List[torch.nn.Parameter]:
+        return self.node_reps
+
+    def __repr__(self) -> str:
+        s = ''
+        s += 'Icosagon one-hot input layer\n'
+        s += '  # of node types: %d\n' % len(self.data.node_types)
+        for nt in self.data.node_types:
+            s += '    - %s (%d)\n' % (nt.name, nt.count)
+        return s.strip()
diff --git a/src/triacontagon/normalize.py b/src/triacontagon/normalize.py
new file mode 100644
index 0000000..e13fb05
--- /dev/null
+++ b/src/triacontagon/normalize.py
@@ -0,0 +1,145 @@
+#
+# Copyright (C) Stanislaw Adaszewski, 2020
+# License: GPLv3
+#
+
+
+import numpy as np
+import scipy.sparse as sp
+import torch
+
+
+def _check_tensor(adj_mat):
+    if not isinstance(adj_mat, torch.Tensor):
+        raise ValueError('adj_mat must be a torch.Tensor')
+
+
+def _check_sparse(adj_mat):
+    if not adj_mat.is_sparse:
+        raise ValueError('adj_mat must be sparse')
+
+
+def _check_dense(adj_mat):
+    if adj_mat.is_sparse:
+        raise ValueError('adj_mat must be dense')
+
+
+def _check_square(adj_mat):
+    if len(adj_mat.shape) != 2 or \
+        adj_mat.shape[0] != adj_mat.shape[1]:
+        raise ValueError('adj_mat must be a square matrix')
+
+
+def _check_2d(adj_mat):
+    if len(adj_mat.shape) != 2:
+        raise ValueError('adj_mat must be a square matrix')
+
+
+def _sparse_coo_tensor(indices, values, size):
+    ctor = { torch.float32: torch.sparse.FloatTensor,
+        torch.float32: torch.sparse.DoubleTensor,
+        torch.uint8: torch.sparse.ByteTensor,
+        torch.long: torch.sparse.LongTensor,
+        torch.int: torch.sparse.IntTensor,
+        torch.short: torch.sparse.ShortTensor,
+        torch.bool: torch.sparse.ByteTensor }[values.dtype]
+    return ctor(indices, values, size)
+
+
+def add_eye_sparse(adj_mat: torch.Tensor) -> torch.Tensor:
+    _check_tensor(adj_mat)
+    _check_sparse(adj_mat)
+    _check_square(adj_mat)
+
+    adj_mat = adj_mat.coalesce()
+    indices = adj_mat.indices()
+    values = adj_mat.values()
+
+    eye_indices = torch.arange(adj_mat.shape[0], dtype=indices.dtype,
+        device=adj_mat.device).view(1, -1)
+    eye_indices = torch.cat((eye_indices, eye_indices), 0)
+    eye_values = torch.ones(adj_mat.shape[0], dtype=values.dtype,
+        device=adj_mat.device)
+
+    indices = torch.cat((indices, eye_indices), 1)
+    values = torch.cat((values, eye_values), 0)
+
+    adj_mat = _sparse_coo_tensor(indices, values, adj_mat.shape)
+
+    return adj_mat
+
+
+def norm_adj_mat_one_node_type_sparse(adj_mat: torch.Tensor) -> torch.Tensor:
+    _check_tensor(adj_mat)
+    _check_sparse(adj_mat)
+    _check_square(adj_mat)
+
+    adj_mat = add_eye_sparse(adj_mat)
+    adj_mat = norm_adj_mat_two_node_types_sparse(adj_mat)
+
+    return adj_mat
+
+
+def norm_adj_mat_one_node_type_dense(adj_mat: torch.Tensor) -> torch.Tensor:
+    _check_tensor(adj_mat)
+    _check_dense(adj_mat)
+    _check_square(adj_mat)
+
+    adj_mat = adj_mat + torch.eye(adj_mat.shape[0], dtype=adj_mat.dtype,
+        device=adj_mat.device)
+    adj_mat = norm_adj_mat_two_node_types_dense(adj_mat)
+
+    return adj_mat
+
+
+def norm_adj_mat_one_node_type(adj_mat: torch.Tensor) -> torch.Tensor:
+    _check_tensor(adj_mat)
+    _check_square(adj_mat)
+
+    if adj_mat.is_sparse:
+        return norm_adj_mat_one_node_type_sparse(adj_mat)
+    else:
+        return norm_adj_mat_one_node_type_dense(adj_mat)
+
+
+def norm_adj_mat_two_node_types_sparse(adj_mat: torch.Tensor) -> torch.Tensor:
+    _check_tensor(adj_mat)
+    _check_sparse(adj_mat)
+    _check_2d(adj_mat)
+
+    adj_mat = adj_mat.coalesce()
+    indices = adj_mat.indices()
+    values = adj_mat.values()
+    degrees_row = torch.zeros(adj_mat.shape[0], device=adj_mat.device)
+    degrees_row = degrees_row.index_add(0, indices[0], values.to(degrees_row.dtype))
+    degrees_col = torch.zeros(adj_mat.shape[1], device=adj_mat.device)
+    degrees_col = degrees_col.index_add(0, indices[1], values.to(degrees_col.dtype))
+    values = values.to(degrees_row.dtype) / torch.sqrt(degrees_row[indices[0]] * degrees_col[indices[1]])
+    adj_mat = _sparse_coo_tensor(indices, values, adj_mat.shape)
+
+    return adj_mat
+
+
+def norm_adj_mat_two_node_types_dense(adj_mat: torch.Tensor) -> torch.Tensor:
+    _check_tensor(adj_mat)
+    _check_dense(adj_mat)
+    _check_2d(adj_mat)
+
+    degrees_row = adj_mat.sum(1).view(-1, 1).to(torch.float32)
+    degrees_col = adj_mat.sum(0).view(1, -1).to(torch.float32)
+    degrees_row = torch.sqrt(degrees_row)
+    degrees_col = torch.sqrt(degrees_col)
+    adj_mat = adj_mat.to(degrees_row.dtype) / degrees_row
+    adj_mat = adj_mat / degrees_col
+
+    return adj_mat
+
+
+def norm_adj_mat_two_node_types(adj_mat: torch.Tensor) -> torch.Tensor:
+    _check_tensor(adj_mat)
+    _check_2d(adj_mat)
+
+    if adj_mat.is_sparse:
+        return norm_adj_mat_two_node_types_sparse(adj_mat)
+    else:
+        return norm_adj_mat_two_node_types_dense(adj_mat)
diff --git a/src/triacontagon/sampling.py b/src/triacontagon/sampling.py
new file mode 100644
index 0000000..7c55944
--- /dev/null
+++ b/src/triacontagon/sampling.py
@@ -0,0 +1,47 @@
+#
+# Copyright (C) Stanislaw Adaszewski, 2020
+# License: GPLv3
+#
+
+
+import numpy as np
+import torch
+import torch.utils.data
+from typing import List, \
+    Union
+
+
+def fixed_unigram_candidate_sampler(
+    true_classes: Union[np.array, torch.Tensor],
+    unigrams: List[Union[int, float]],
+    distortion: float = 1.):
+
+    if isinstance(true_classes, torch.Tensor):
+        true_classes = true_classes.detach().cpu().numpy()
+
+    if isinstance(unigrams, torch.Tensor):
+        unigrams = unigrams.detach().cpu().numpy()
+
+    if len(true_classes.shape) != 2:
+        raise ValueError('true_classes must be a 2D matrix with shape (num_samples, num_true)')
+        
+    num_samples = true_classes.shape[0]
+    unigrams = np.array(unigrams)
+    if distortion != 1.:
+        unigrams = unigrams.astype(np.float64) ** distortion
+    # print('unigrams:', unigrams)
+    indices = np.arange(num_samples)
+    result = np.zeros(num_samples, dtype=np.int64)
+    while len(indices) > 0:
+        # print('len(indices):', len(indices))
+        sampler = torch.utils.data.WeightedRandomSampler(unigrams, len(indices))
+        candidates = np.array(list(sampler))
+        candidates = np.reshape(candidates, (len(indices), 1))
+        # print('candidates:', candidates)
+        # print('true_classes:', true_classes[indices, :])
+        result[indices] = candidates.T
+        mask = (candidates == true_classes[indices, :])
+        mask = mask.sum(1).astype(np.bool)
+        # print('mask:', mask)
+        indices = indices[mask]
+    return torch.tensor(result)
diff --git a/src/triacontagon/trainprep.py b/src/triacontagon/trainprep.py
new file mode 100644
index 0000000..c49300a
--- /dev/null
+++ b/src/triacontagon/trainprep.py
@@ -0,0 +1,215 @@
+#
+# Copyright (C) Stanislaw Adaszewski, 2020
+# License: GPLv3
+#
+
+
+from .sampling import fixed_unigram_candidate_sampler
+import torch
+from dataclasses import dataclass, \
+    field
+from typing import Any, \
+    List, \
+    Tuple, \
+    Dict
+from .data import NodeType, \
+    RelationType, \
+    RelationTypeBase, \
+    RelationFamily, \
+    RelationFamilyBase, \
+    Data
+from collections import defaultdict
+from .normalize import norm_adj_mat_one_node_type, \
+    norm_adj_mat_two_node_types
+import numpy as np
+
+
+@dataclass
+class TrainValTest(object):
+    train: Any
+    val: Any
+    test: Any
+
+
+@dataclass
+class PreparedRelationType(RelationTypeBase):
+    edges_pos: TrainValTest
+    edges_neg: TrainValTest
+    edges_back_pos: TrainValTest
+    edges_back_neg: TrainValTest
+
+
+@dataclass
+class PreparedRelationFamily(RelationFamilyBase):
+    relation_types: List[PreparedRelationType]
+
+
+@dataclass
+class PreparedData(object):
+    node_types: List[NodeType]
+    relation_families: List[PreparedRelationFamily]
+
+
+def _empty_edge_list_tvt() -> TrainValTest:
+    return TrainValTest(*[ torch.zeros((0, 2), dtype=torch.long) for _ in range(3) ])
+
+
+def train_val_test_split_edges(edges: torch.Tensor,
+    ratios: TrainValTest) -> TrainValTest:
+
+    if not isinstance(edges, torch.Tensor):
+        raise ValueError('edges must be a torch.Tensor')
+
+    if len(edges.shape) != 2 or edges.shape[1] != 2:
+        raise ValueError('edges shape must be (num_edges, 2)')
+
+    if not isinstance(ratios, TrainValTest):
+        raise ValueError('ratios must be a TrainValTest')
+
+    if ratios.train + ratios.val + ratios.test != 1.0:
+        raise ValueError('Train, validation and test ratios must add up to 1')
+
+    order = torch.randperm(len(edges))
+    edges = edges[order, :]
+    n = round(len(edges) * ratios.train)
+    edges_train = edges[:n]
+    n_1 = round(len(edges) * (ratios.train + ratios.val))
+    edges_val = edges[n:n_1]
+    edges_test = edges[n_1:]
+
+    return TrainValTest(edges_train, edges_val, edges_test)
+
+
+def get_edges_and_degrees(adj_mat: torch.Tensor) -> Tuple[torch.Tensor, torch.Tensor]:
+    if adj_mat.is_sparse:
+        adj_mat = adj_mat.coalesce()
+        degrees = torch.zeros(adj_mat.shape[1], dtype=torch.int64,
+            device=adj_mat.device)
+        degrees = degrees.index_add(0, adj_mat.indices()[1],
+            torch.ones(adj_mat.indices().shape[1], dtype=torch.int64,
+                device=adj_mat.device))
+        edges_pos = adj_mat.indices().transpose(0, 1)
+    else:
+        degrees = adj_mat.sum(0)
+        edges_pos = torch.nonzero(adj_mat)
+    return edges_pos, degrees
+
+
+def prepare_adj_mat(adj_mat: torch.Tensor,
+    ratios: TrainValTest) -> Tuple[TrainValTest, TrainValTest]:
+
+    if not isinstance(adj_mat, torch.Tensor):
+        raise ValueError('adj_mat must be a torch.Tensor')
+
+    edges_pos, degrees = get_edges_and_degrees(adj_mat)
+
+    neg_neighbors = fixed_unigram_candidate_sampler(
+        edges_pos[:, 1].view(-1, 1), degrees, 0.75).to(adj_mat.device)
+    print(edges_pos.dtype)
+    print(neg_neighbors.dtype)
+    edges_neg = torch.cat((edges_pos[:, 0].view(-1, 1), neg_neighbors.view(-1, 1)), 1)
+
+    edges_pos = train_val_test_split_edges(edges_pos, ratios)
+    edges_neg = train_val_test_split_edges(edges_neg, ratios)
+
+    adj_mat_train = torch.sparse_coo_tensor(indices = edges_pos.train.transpose(0, 1),
+        values=torch.ones(len(edges_pos.train)), size=adj_mat.shape, dtype=adj_mat.dtype,
+        device=adj_mat.device)
+
+    return adj_mat_train, edges_pos, edges_neg
+
+
+def prep_rel_one_node_type(r: RelationType,
+    ratios: TrainValTest) -> PreparedRelationType:
+
+    adj_mat = r.adjacency_matrix
+    adj_mat_train, edges_pos, edges_neg = prepare_adj_mat(adj_mat, ratios)
+    adj_mat_back_train, edges_back_pos, edges_back_neg = \
+        None, _empty_edge_list_tvt(), _empty_edge_list_tvt()
+
+    print('adj_mat_train:', adj_mat_train)
+    adj_mat_train = norm_adj_mat_one_node_type(adj_mat_train)
+
+    return PreparedRelationType(r.name, r.node_type_row, r.node_type_column,
+        adj_mat_train, adj_mat_back_train, edges_pos, edges_neg,
+        edges_back_pos, edges_back_neg)
+
+
+def prep_rel_two_node_types_sym(r: RelationType,
+    ratios: TrainValTest) -> PreparedRelationType:
+
+    adj_mat = r.adjacency_matrix
+    adj_mat_train, edges_pos, edges_neg = prepare_adj_mat(adj_mat, ratios)
+    edges_back_pos, edges_back_neg = \
+        _empty_edge_list_tvt(), _empty_edge_list_tvt()
+
+    return PreparedRelationType(r.name, r.node_type_row,
+        r.node_type_column,
+        norm_adj_mat_two_node_types(adj_mat_train),
+        norm_adj_mat_two_node_types(adj_mat_train.transpose(0, 1)),
+        edges_pos, edges_neg, edges_back_pos, edges_back_neg)
+
+
+def prep_rel_two_node_types_asym(r: RelationType,
+    ratios: TrainValTest) -> PreparedRelationType:
+
+    if r.adjacency_matrix is not None:
+        adj_mat_train, edges_pos, edges_neg =\
+            prepare_adj_mat(r.adjacency_matrix, ratios)
+    else:
+        adj_mat_train, edges_pos, edges_neg = \
+            None, _empty_edge_list_tvt(), _empty_edge_list_tvt()
+
+    if r.adjacency_matrix_backward is not None:
+        adj_mat_back_train, edges_back_pos, edges_back_neg = \
+            prepare_adj_mat(r.adjacency_matrix_backward, ratios)
+    else:
+        adj_mat_back_train, edges_back_pos, edges_back_neg = \
+            None, _empty_edge_list_tvt(), _empty_edge_list_tvt()
+
+    return PreparedRelationType(r.name, r.node_type_row,
+        r.node_type_column,
+        norm_adj_mat_two_node_types(adj_mat_train),
+        norm_adj_mat_two_node_types(adj_mat_back_train),
+        edges_pos, edges_neg, edges_back_pos, edges_back_neg)
+
+
+def prepare_relation_type(r: RelationType,
+    ratios: TrainValTest, is_symmetric: bool) -> PreparedRelationType:
+
+    if not isinstance(r, RelationType):
+        raise ValueError('r must be a RelationType')
+
+    if not isinstance(ratios, TrainValTest):
+        raise ValueError('ratios must be a TrainValTest')
+
+    if r.node_type_row == r.node_type_column:
+        return prep_rel_one_node_type(r, ratios)
+    elif is_symmetric:
+        return prep_rel_two_node_types_sym(r, ratios)
+    else:
+        return prep_rel_two_node_types_asym(r, ratios)
+
+
+def prepare_relation_family(fam: RelationFamily,
+    ratios: TrainValTest) -> PreparedRelationFamily:
+
+    relation_types = []
+
+    for r in fam.relation_types:
+        relation_types.append(prepare_relation_type(r, ratios, fam.is_symmetric))
+
+    return PreparedRelationFamily(fam.data, fam.name,
+        fam.node_type_row, fam.node_type_column,
+        fam.is_symmetric, fam.decoder_class,
+        relation_types)
+
+
+def prepare_training(data: Data, ratios: TrainValTest) -> PreparedData:
+    if not isinstance(data, Data):
+        raise ValueError('data must be of class Data')
+
+    relation_families = [ prepare_relation_family(fam, ratios) \
+        for fam in data.relation_families ]
+
+    return PreparedData(data.node_types, relation_families)
diff --git a/src/triacontagon/weights.py b/src/triacontagon/weights.py
new file mode 100644
index 0000000..2dcb7b4
--- /dev/null
+++ b/src/triacontagon/weights.py
@@ -0,0 +1,19 @@
+#
+# Copyright (C) Stanislaw Adaszewski, 2020
+# License: GPLv3
+#
+
+
+import torch
+import numpy as np
+
+
+def init_glorot(in_channels, out_channels, dtype=torch.float32):
+    """Create a weight variable with Glorot & Bengio (AISTATS 2010)
+    initialization.
+    """
+    init_range = np.sqrt(6.0 / (in_channels + out_channels))
+    initial = -init_range + 2 * init_range * \
+        torch.rand(( in_channels, out_channels ), dtype=dtype)
+    initial = initial.requires_grad_(True)
+    return initial