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"""!
@brief Neural Network: Self-Organized Feature Map
@details Implementation based on paper @cite article::nnet::som::1, @cite article::nnet::som::2.
@authors Andrei Novikov (pyclustering@yandex.ru)
@date 2014-2020
@copyright BSD-3-Clause
"""
import math
import random
import matplotlib.pyplot as plt
import pyclustering.core.som_wrapper as wrapper
from pyclustering.core.wrapper import ccore_library
from pyclustering.utils import euclidean_distance_square
from pyclustering.utils.dimension import dimension_info
from enum import IntEnum
class type_conn(IntEnum):
"""!
@brief Enumeration of connection types for SOM.
@see som
"""
## Grid type of connections when each oscillator has connections with left, upper, right, lower neighbors.
grid_four = 0
## Grid type of connections when each oscillator has connections with left, upper-left, upper, upper-right, right, right-lower, lower, lower-left neighbors.
grid_eight = 1
## Grid type of connections when each oscillator has connections with left, upper-left, upper-right, right, right-lower, lower-left neighbors.
honeycomb = 2
## Grid type of connections when existance of each connection is defined by the SOM rule on each step of simulation.
func_neighbor = 3
class type_init(IntEnum):
"""!
@brief Enumeration of initialization types for SOM.
@see som
"""
## Weights are randomly distributed using Gaussian distribution (0, 1).
random = 0
## Weights are randomly distributed using Gaussian distribution (input data centroid, 1).
random_centroid = 1
## Weights are randomly distrbiuted using Gaussian distribution (input data centroid, surface of input data).
random_surface = 2
## Weights are distributed as a uniform grid that covers whole surface of the input data.
uniform_grid = 3
class som_parameters:
"""!
@brief Represents SOM parameters.
"""
def __init__(self):
"""!
@brief Creates SOM parameters.
"""
## Defines an initialization way for neuron weights (random, random in center of the input data, random distributed in data, ditributed in line with uniform grid).
self.init_type = type_init.uniform_grid
## Initial radius. If the initial radius is not specified (equals to `None`) then it will be calculated by SOM.
self.init_radius = None
## Rate of learning.
self.init_learn_rate = 0.1
## Condition that defines when the learining process should be stopped. It is used when the autostop mode is on.
self.adaptation_threshold = 0.001
## Seed for random state (by default is `None`, current system time is used).
self.random_state = None
class som:
"""!
@brief Represents self-organized feature map (SOM).
@details The self-organizing feature map (SOM) method is a powerful tool for the visualization of
of high-dimensional data. It converts complex, nonlinear statistical relationships between
high-dimensional data into simple geometric relationships on a low-dimensional display.
@details `ccore` option can be specified in order to control using C++ implementation of pyclustering library. By
default C++ implementation is on. C++ implementation improves performance of the self-organized feature
map.
Example:
@code
import random
from pyclustering.utils import read_sample
from pyclustering.nnet.som import som, type_conn, type_init, som_parameters
from pyclustering.samples.definitions import FCPS_SAMPLES
# read sample 'Lsun' from file
sample = read_sample(FCPS_SAMPLES.SAMPLE_LSUN)
# create SOM parameters
parameters = som_parameters()
# create self-organized feature map with size 7x7
rows = 10 # five rows
cols = 10 # five columns
structure = type_conn.grid_four; # each neuron has max. four neighbors.
network = som(rows, cols, structure, parameters)
# train network on 'Lsun' sample during 100 epouchs.
network.train(sample, 100)
# simulate trained network using randomly modified point from input dataset.
index_point = random.randint(0, len(sample) - 1)
point = sample[index_point] # obtain randomly point from data
point[0] += random.random() * 0.2 # change randomly X-coordinate
point[1] += random.random() * 0.2 # change randomly Y-coordinate
index_winner = network.simulate(point)
# check what are objects from input data are much close to randomly modified.
index_similar_objects = network.capture_objects[index_winner]
# neuron contains information of encoded objects
print("Point '%s' is similar to objects with indexes '%s'." % (str(point), str(index_similar_objects)))
print("Coordinates of similar objects:")
for index in index_similar_objects: print("\tPoint:", sample[index])
# result visualization:
# show distance matrix (U-matrix).
network.show_distance_matrix()
# show density matrix (P-matrix).
network.show_density_matrix()
# show winner matrix.
network.show_winner_matrix()
# show self-organized map.
network.show_network()
@endcode
There is a visualization of 'Target' sample that was done by the self-organized feature map:
@image html target_som_processing.png
"""
@property
def size(self):
"""!
@brief Return size of self-organized map that is defined by total number of neurons.
@return (uint) Size of self-organized map (number of neurons).
"""
if self.__ccore_som_pointer is not None:
self._size = wrapper.som_get_size(self.__ccore_som_pointer)
return self._size
@property
def weights(self):
"""!
@brief Return weight of each neuron.
@return (list) Weights of each neuron.
"""
if self.__ccore_som_pointer is not None:
self._weights = wrapper.som_get_weights(self.__ccore_som_pointer)
return self._weights
@property
def awards(self):
"""!
@brief Return amount of captured objects by each neuron after training.
@return (list) Amount of captured objects by each neuron.
@see train()
"""
if self.__ccore_som_pointer is not None:
self._award = wrapper.som_get_awards(self.__ccore_som_pointer)
return self._award
@property
def capture_objects(self):
"""!
@brief Returns indexes of captured objects by each neuron.
@details For example, a network with size 2x2 has been trained on a sample with five objects. Suppose neuron #1
won an object with index `1`, neuron #2 won objects `0`, `3`, `4`, neuron #3 did not won anything and
finally neuron #4 won an object with index `2`. Thus, for this example we will have the following
output `[[1], [0, 3, 4], [], [2]]`.
@return (list) Indexes of captured objects by each neuron.
"""
if self.__ccore_som_pointer is not None:
self._capture_objects = wrapper.som_get_capture_objects(self.__ccore_som_pointer)
return self._capture_objects
def __init__(self, rows, cols, conn_type=type_conn.grid_eight, parameters=None, ccore=True):
"""!
@brief Constructor of self-organized map.
@param[in] rows (uint): Number of neurons in the column (number of rows).
@param[in] cols (uint): Number of neurons in the row (number of columns).
@param[in] conn_type (type_conn): Type of connection between oscillators in the network (grid four, grid eight, honeycomb, function neighbour).
@param[in] parameters (som_parameters): Other specific parameters.
@param[in] ccore (bool): If True simulation is performed by CCORE library (C++ implementation of pyclustering).
"""
# some of these parameters are required despite core implementation, for example, for network visualization.
self._cols = cols
self._rows = rows
self._size = cols * rows
self._conn_type = conn_type
self._data = None
self._neighbors = None
self._local_radius = 0.0
self._learn_rate = 0.0
self.__ccore_som_pointer = None
self._params = parameters or som_parameters()
if self._params.init_radius is None:
self._params.init_radius = self.__initialize_initial_radius(rows, cols)
if (ccore is True) and ccore_library.workable():
self.__ccore_som_pointer = wrapper.som_create(rows, cols, conn_type, self._params)
else:
# location
self._location = self.__initialize_locations(rows, cols)
# default weights
self._weights = [[0.0]] * self._size
# awards
self._award = [0] * self._size
# captured objects
self._capture_objects = [[] for i in range(self._size)]
# distances - calculate and store them only during training
self._sqrt_distances = None
# connections
if conn_type != type_conn.func_neighbor:
self._create_connections(conn_type)
def __del__(self):
"""!
@brief Destructor of the self-organized feature map.
"""
if self.__ccore_som_pointer is not None:
wrapper.som_destroy(self.__ccore_som_pointer)
def __len__(self):
"""!
@brief Returns size of the network that defines by amount of neuron in it.
@return (uint) Size of self-organized map (amount of neurons).
"""
return self._size
def __getstate__(self):
"""
@brief Returns state of SOM network that can be used to store network.
"""
if self.__ccore_som_pointer is not None:
self.__download_dump_from_ccore()
return self.__get_dump_from_python(True)
return self.__get_dump_from_python(False)
def __setstate__(self, som_state):
"""
@brief Set state of SOM network that can be used to load network.
"""
if som_state['ccore'] is True and ccore_library.workable():
self.__upload_dump_to_ccore(som_state['state'])
else:
self.__upload_dump_to_python(som_state['state'])
def __initialize_initial_radius(self, rows, cols):
"""!
@brief Initialize initial radius using map sizes.
@param[in] rows (uint): Number of neurons in the column (number of rows).
@param[in] cols (uint): Number of neurons in the row (number of columns).
@return (list) Value of initial radius.
"""
if (cols + rows) / 4.0 > 1.0:
return 2.0
elif (cols > 1) and (rows > 1):
return 1.5
else:
return 1.0
def __initialize_locations(self, rows, cols):
"""!
@brief Initialize locations (coordinates in SOM grid) of each neurons in the map.
@param[in] rows (uint): Number of neurons in the column (number of rows).
@param[in] cols (uint): Number of neurons in the row (number of columns).
@return (list) List of coordinates of each neuron in map.
"""
location = list()
for i in range(rows):
for j in range(cols):
location.append([float(i), float(j)])
return location
def __initialize_distances(self, size, location):
"""!
@brief Initialize distance matrix in SOM grid.
@param[in] size (uint): Amount of neurons in the network.
@param[in] location (list): List of coordinates of each neuron in the network.
@return (list) Distance matrix between neurons in the network.
"""
sqrt_distances = [[[] for i in range(size)] for j in range(size)]
for i in range(size):
for j in range(i, size, 1):
dist = euclidean_distance_square(location[i], location[j])
sqrt_distances[i][j] = dist
sqrt_distances[j][i] = dist
return sqrt_distances
def _create_initial_weights(self, init_type):
"""!
@brief Creates initial weights for neurons in line with the specified initialization.
@param[in] init_type (type_init): Type of initialization of initial neuron weights (random, random in center of the input data, random distributed in data, ditributed in line with uniform grid).
"""
dim_info = dimension_info(self._data)
step_x = dim_info.get_center()[0]
if self._rows > 1:
step_x = dim_info.get_width()[0] / (self._rows - 1)
step_y = 0.0
if dim_info.get_dimensions() > 1:
step_y = dim_info.get_center()[1]
if self._cols > 1:
step_y = dim_info.get_width()[1] / (self._cols - 1)
# generate weights (topological coordinates)
random.seed(self._params.random_state)
# Uniform grid.
if init_type == type_init.uniform_grid:
# Predefined weights in line with input data.
self._weights = [[[] for i in range(dim_info.get_dimensions())] for j in range(self._size)]
for i in range(self._size):
location = self._location[i]
for dim in range(dim_info.get_dimensions()):
if dim == 0:
if self._rows > 1:
self._weights[i][dim] = dim_info.get_minimum_coordinate()[dim] + step_x * location[dim]
else:
self._weights[i][dim] = dim_info.get_center()[dim]
elif dim == 1:
if self._cols > 1:
self._weights[i][dim] = dim_info.get_minimum_coordinate()[dim] + step_y * location[dim]
else:
self._weights[i][dim] = dim_info.get_center()[dim]
else:
self._weights[i][dim] = dim_info.get_center()[dim]
elif init_type == type_init.random_surface:
# Random weights at the full surface.
self._weights = [
[random.uniform(dim_info.get_minimum_coordinate()[i], dim_info.get_maximum_coordinate()[i]) for i in
range(dim_info.get_dimensions())] for _ in range(self._size)]
elif init_type == type_init.random_centroid:
# Random weights at the center of input data.
self._weights = [[(random.random() + dim_info.get_center()[i]) for i in range(dim_info.get_dimensions())]
for _ in range(self._size)]
else:
# Random weights of input data.
self._weights = [[random.random() for i in range(dim_info.get_dimensions())] for _ in range(self._size)]
def _create_connections(self, conn_type):
"""!
@brief Create connections in line with input rule (grid four, grid eight, honeycomb, function neighbour).
@param[in] conn_type (type_conn): Type of connection between oscillators in the network.
"""
self._neighbors = [[] for index in range(self._size)]
for index in range(0, self._size, 1):
upper_index = index - self._cols
upper_left_index = index - self._cols - 1
upper_right_index = index - self._cols + 1
lower_index = index + self._cols
lower_left_index = index + self._cols - 1
lower_right_index = index + self._cols + 1
left_index = index - 1
right_index = index + 1
node_row_index = math.floor(index / self._cols)
upper_row_index = node_row_index - 1
lower_row_index = node_row_index + 1
if (conn_type == type_conn.grid_eight) or (conn_type == type_conn.grid_four):
if upper_index >= 0:
self._neighbors[index].append(upper_index)
if lower_index < self._size:
self._neighbors[index].append(lower_index)
if (conn_type == type_conn.grid_eight) or (conn_type == type_conn.grid_four) or (
conn_type == type_conn.honeycomb):
if (left_index >= 0) and (math.floor(left_index / self._cols) == node_row_index):
self._neighbors[index].append(left_index)
if (right_index < self._size) and (math.floor(right_index / self._cols) == node_row_index):
self._neighbors[index].append(right_index)
if conn_type == type_conn.grid_eight:
if (upper_left_index >= 0) and (math.floor(upper_left_index / self._cols) == upper_row_index):
self._neighbors[index].append(upper_left_index)
if (upper_right_index >= 0) and (math.floor(upper_right_index / self._cols) == upper_row_index):
self._neighbors[index].append(upper_right_index)
if (lower_left_index < self._size) and (math.floor(lower_left_index / self._cols) == lower_row_index):
self._neighbors[index].append(lower_left_index)
if (lower_right_index < self._size) and (math.floor(lower_right_index / self._cols) == lower_row_index):
self._neighbors[index].append(lower_right_index)
if conn_type == type_conn.honeycomb:
if (node_row_index % 2) == 0:
upper_left_index = index - self._cols
upper_right_index = index - self._cols + 1
lower_left_index = index + self._cols
lower_right_index = index + self._cols + 1
else:
upper_left_index = index - self._cols - 1
upper_right_index = index - self._cols
lower_left_index = index + self._cols - 1
lower_right_index = index + self._cols
if (upper_left_index >= 0) and (math.floor(upper_left_index / self._cols) == upper_row_index):
self._neighbors[index].append(upper_left_index)
if (upper_right_index >= 0) and (math.floor(upper_right_index / self._cols) == upper_row_index):
self._neighbors[index].append(upper_right_index)
if (lower_left_index < self._size) and (math.floor(lower_left_index / self._cols) == lower_row_index):
self._neighbors[index].append(lower_left_index)
if (lower_right_index < self._size) and (math.floor(lower_right_index / self._cols) == lower_row_index):
self._neighbors[index].append(lower_right_index)
def _competition(self, x):
"""!
@brief Calculates neuron winner (distance, neuron index).
@param[in] x (list): Input pattern from the input data set, for example it can be coordinates of point.
@return (uint) Returns index of neuron that is winner.
"""
index = 0
minimum = euclidean_distance_square(self._weights[0], x)
for i in range(1, self._size, 1):
candidate = euclidean_distance_square(self._weights[i], x)
if candidate < minimum:
index = i
minimum = candidate
return index
def _adaptation(self, index, x):
"""!
@brief Change weight of neurons in line with won neuron.
@param[in] index (uint): Index of neuron-winner.
@param[in] x (list): Input pattern from the input data set.
"""
dimension = len(self._weights[0])
if self._conn_type == type_conn.func_neighbor:
for neuron_index in range(self._size):
distance = self._sqrt_distances[index][neuron_index]
if distance < self._local_radius:
influence = math.exp(-(distance / (2.0 * self._local_radius)))
for i in range(dimension):
self._weights[neuron_index][i] = self._weights[neuron_index][
i] + self._learn_rate * influence * (
x[i] - self._weights[neuron_index][i])
else:
for i in range(dimension):
self._weights[index][i] = self._weights[index][i] + self._learn_rate * (x[i] - self._weights[index][i])
for neighbor_index in self._neighbors[index]:
distance = self._sqrt_distances[index][neighbor_index]
if distance < self._local_radius:
influence = math.exp(-(distance / (2.0 * self._local_radius)))
for i in range(dimension):
self._weights[neighbor_index][i] = self._weights[neighbor_index][
i] + self._learn_rate * influence * (
x[i] - self._weights[neighbor_index][i])
def train(self, data, epochs, autostop=False):
"""!
@brief Trains self-organized feature map (SOM).
@param[in] data (list): Input data - list of points where each point is represented by list of features, for example coordinates.
@param[in] epochs (uint): Number of epochs for training.
@param[in] autostop (bool): Automatic termination of learning process when adaptation is not occurred.
@return (uint) Number of learning iterations.
"""
self._data = data
if self.__ccore_som_pointer is not None:
return wrapper.som_train(self.__ccore_som_pointer, data, epochs, autostop)
self._sqrt_distances = self.__initialize_distances(self._size, self._location)
for i in range(self._size):
self._award[i] = 0
self._capture_objects[i].clear()
# weights
self._create_initial_weights(self._params.init_type)
previous_weights = None
for epoch in range(1, epochs + 1):
# Depression term of coupling
self._local_radius = (self._params.init_radius * math.exp(-(epoch / epochs))) ** 2
self._learn_rate = self._params.init_learn_rate * math.exp(-(epoch / epochs))
# Clear statistics
if autostop:
for i in range(self._size):
self._award[i] = 0
self._capture_objects[i].clear()
for i in range(len(self._data)):
# Step 1: Competition:
index = self._competition(self._data[i])
# Step 2: Adaptation:
self._adaptation(index, self._data[i])
# Update statistics
if (autostop is True) or (epoch == epochs):
self._award[index] += 1
self._capture_objects[index].append(i)
# Check requirement of stopping
if autostop:
if previous_weights is not None:
maximal_adaptation = self._get_maximal_adaptation(previous_weights)
if maximal_adaptation < self._params.adaptation_threshold:
return epoch
previous_weights = [item[:] for item in self._weights]
return epochs
def simulate(self, input_pattern):
"""!
@brief Processes input pattern (no learining) and returns index of neuron-winner.
Using index of neuron winner catched object can be obtained using property capture_objects.
@param[in] input_pattern (list): Input pattern.
@return (uint) Returns index of neuron-winner.
@see capture_objects
"""
if self.__ccore_som_pointer is not None:
return wrapper.som_simulate(self.__ccore_som_pointer, input_pattern)
return self._competition(input_pattern)
def _get_maximal_adaptation(self, previous_weights):
"""!
@brief Calculates maximum changes of weight in line with comparison between previous weights and current weights.
@param[in] previous_weights (list): Weights from the previous step of learning process.
@return (double) Value that represents maximum changes of weight after adaptation process.
"""
dimension = len(self._data[0])
maximal_adaptation = 0.0
for neuron_index in range(self._size):
for dim in range(dimension):
current_adaptation = previous_weights[neuron_index][dim] - self._weights[neuron_index][dim]
if current_adaptation < 0:
current_adaptation = -current_adaptation
if maximal_adaptation < current_adaptation:
maximal_adaptation = current_adaptation
return maximal_adaptation
def get_winner_number(self):
"""!
@brief Calculates number of winner at the last step of learning process.
@return (uint) Number of winner.
"""
if self.__ccore_som_pointer is not None:
self._award = wrapper.som_get_awards(self.__ccore_som_pointer)
winner_number = 0
for i in range(self._size):
if self._award[i] > 0:
winner_number += 1
return winner_number
def show_distance_matrix(self):
"""!
@brief Shows gray visualization of U-matrix (distance matrix).
@see get_distance_matrix()
"""
distance_matrix = self.get_distance_matrix()
plt.imshow(distance_matrix, cmap=plt.get_cmap('hot'), interpolation='kaiser')
plt.title("U-Matrix")
plt.colorbar()
plt.show()
def get_distance_matrix(self):
"""!
@brief Calculates distance matrix (U-matrix).
@details The U-Matrix visualizes based on the distance in input space between a weight vector and its neighbors on map.
@return (list) Distance matrix (U-matrix).
@see show_distance_matrix()
@see get_density_matrix()
"""
if self.__ccore_som_pointer is not None:
self._weights = wrapper.som_get_weights(self.__ccore_som_pointer)
if self._conn_type != type_conn.func_neighbor:
self._neighbors = wrapper.som_get_neighbors(self.__ccore_som_pointer)
distance_matrix = [[0.0] * self._cols for i in range(self._rows)]
for i in range(self._rows):
for j in range(self._cols):
neuron_index = i * self._cols + j
if self._conn_type == type_conn.func_neighbor:
self._create_connections(type_conn.grid_eight)
for neighbor_index in self._neighbors[neuron_index]:
distance_matrix[i][j] += euclidean_distance_square(self._weights[neuron_index],
self._weights[neighbor_index])
distance_matrix[i][j] /= len(self._neighbors[neuron_index])
return distance_matrix
def show_density_matrix(self, surface_divider=20.0):
"""!
@brief Show density matrix (P-matrix) using kernel density estimation.
@param[in] surface_divider (double): Divider in each dimension that affect radius for density measurement.
@see show_distance_matrix()
"""
density_matrix = self.get_density_matrix(surface_divider)
plt.imshow(density_matrix, cmap=plt.get_cmap('hot'), interpolation='kaiser')
plt.title("P-Matrix")
plt.colorbar()
plt.show()
def get_density_matrix(self, surface_divider=20.0):
"""!
@brief Calculates density matrix (P-Matrix).
@param[in] surface_divider (double): Divider in each dimension that affect radius for density measurement.
@return (list) Density matrix (P-Matrix).
@see get_distance_matrix()
"""
if self.__ccore_som_pointer is not None:
self._weights = wrapper.som_get_weights(self.__ccore_som_pointer)
density_matrix = [[0] * self._cols for i in range(self._rows)]
dimension = len(self._weights[0])
dim_max = [float('-Inf')] * dimension
dim_min = [float('Inf')] * dimension
for weight in self._weights:
for index_dim in range(dimension):
if weight[index_dim] > dim_max[index_dim]:
dim_max[index_dim] = weight[index_dim]
if weight[index_dim] < dim_min[index_dim]:
dim_min[index_dim] = weight[index_dim]
radius = [0.0] * len(self._weights[0])
for index_dim in range(dimension):
radius[index_dim] = (dim_max[index_dim] - dim_min[index_dim]) / surface_divider
## TODO: do not use data
for point in self._data:
for index_neuron in range(len(self)):
point_covered = True
for index_dim in range(dimension):
if abs(point[index_dim] - self._weights[index_neuron][index_dim]) > radius[index_dim]:
point_covered = False
break
row = int(math.floor(index_neuron / self._cols))
col = index_neuron - row * self._cols
if point_covered is True:
density_matrix[row][col] += 1
return density_matrix
def show_winner_matrix(self):
"""!
@brief Show a winner matrix where each element corresponds to neuron and value represents
amount of won objects from input data-space at the last training iteration.
@see show_distance_matrix()
"""
if self.__ccore_som_pointer is not None:
self._award = wrapper.som_get_awards(self.__ccore_som_pointer)
(fig, ax) = plt.subplots()
winner_matrix = [[0] * self._cols for _ in range(self._rows)]
for i in range(self._rows):
for j in range(self._cols):
neuron_index = i * self._cols + j
winner_matrix[i][j] = self._award[neuron_index]
ax.text(i, j, str(winner_matrix[i][j]), va='center', ha='center')
ax.imshow(winner_matrix, cmap=plt.get_cmap('cool'), interpolation='none')
ax.grid(True)
plt.title("Winner Matrix")
plt.show()
def show_network(self, awards=False, belongs=False, coupling=True, dataset=True, marker_type='o'):
"""!
@brief Shows neurons in the dimension of data.
@param[in] awards (bool): If True - displays how many objects won each neuron.
@param[in] belongs (bool): If True - marks each won object by according index of neuron-winner (only when
dataset is displayed too).
@param[in] coupling (bool): If True - displays connections between neurons (except case when function neighbor
is used).
@param[in] dataset (bool): If True - displays inputs data set.
@param[in] marker_type (string): Defines marker that is used to denote neurons on the plot.
"""
if self.__ccore_som_pointer is not None:
self._size = wrapper.som_get_size(self.__ccore_som_pointer)
self._weights = wrapper.som_get_weights(self.__ccore_som_pointer)
self._neighbors = wrapper.som_get_neighbors(self.__ccore_som_pointer)
self._award = wrapper.som_get_awards(self.__ccore_som_pointer)
dimension = len(self._weights[0])
fig = plt.figure()
# Check for dimensions
if (dimension == 1) or (dimension == 2):
axes = fig.add_subplot(111)
elif dimension == 3:
axes = fig.gca(projection='3d')
else:
raise NotImplementedError('Impossible to show network in data-space that is differ from 1D, 2D or 3D.')
if (self._data is not None) and (dataset is True):
for x in self._data:
if dimension == 1:
axes.plot(x[0], 0.0, 'b|', ms=30)
elif dimension == 2:
axes.plot(x[0], x[1], 'b.')
elif dimension == 3:
axes.scatter(x[0], x[1], x[2], c='b', marker='.')
# Show neurons
for index in range(self._size):
color = 'g'
if self._award[index] == 0:
color = 'y'
if dimension == 1:
axes.plot(self._weights[index][0], 0.0, color + marker_type)
if awards:
location = '{0}'.format(self._award[index])
axes.text(self._weights[index][0], 0.0, location, color='black', fontsize=10)
if belongs and self._data is not None:
location = '{0}'.format(index)
axes.text(self._weights[index][0], 0.0, location, color='black', fontsize=12)
for k in range(len(self._capture_objects[index])):
point = self._data[self._capture_objects[index][k]]
axes.text(point[0], 0.0, location, color='blue', fontsize=10)
if dimension == 2:
axes.plot(self._weights[index][0], self._weights[index][1], color + marker_type)
if awards:
location = '{0}'.format(self._award[index])
axes.text(self._weights[index][0], self._weights[index][1], location, color='black', fontsize=10)
if belongs and self._data is not None:
location = '{0}'.format(index)
axes.text(self._weights[index][0], self._weights[index][1], location, color='black', fontsize=12)
for k in range(len(self._capture_objects[index])):
point = self._data[self._capture_objects[index][k]]
axes.text(point[0], point[1], location, color='blue', fontsize=10)
if (self._conn_type != type_conn.func_neighbor) and (coupling is True):
for neighbor in self._neighbors[index]:
if neighbor > index:
axes.plot([self._weights[index][0], self._weights[neighbor][0]],
[self._weights[index][1], self._weights[neighbor][1]],
'g', linewidth=0.5)
elif dimension == 3:
axes.scatter(self._weights[index][0], self._weights[index][1], self._weights[index][2], c=color,
marker=marker_type)
if (self._conn_type != type_conn.func_neighbor) and (coupling != False):
for neighbor in self._neighbors[index]:
if neighbor > index:
axes.plot([self._weights[index][0], self._weights[neighbor][0]],
[self._weights[index][1], self._weights[neighbor][1]],
[self._weights[index][2], self._weights[neighbor][2]],
'g-', linewidth=0.5)
plt.title("Network Structure")
plt.grid()
plt.show()
def __get_dump_from_python(self, ccore_usage):
return {'ccore': ccore_usage,
'state': {'cols': self._cols,
'rows': self._rows,
'size': self._size,
'conn_type': self._conn_type,
'neighbors': self._neighbors,
'local_radius': self._local_radius,
'learn_rate': self._learn_rate,
'params': self._params,
'location': self._location,
'weights': self._weights,
'award': self._award,
'capture_objects': self._capture_objects}}
def __download_dump_from_ccore(self):
self._location = self.__initialize_locations(self._rows, self._cols)
self._weights = wrapper.som_get_weights(self.__ccore_som_pointer)
self._award = wrapper.som_get_awards(self.__ccore_som_pointer)
self._capture_objects = wrapper.som_get_capture_objects(self.__ccore_som_pointer)
def __upload_common_part(self, state_dump):
self._cols = state_dump['cols']
self._rows = state_dump['rows']
self._size = state_dump['size']
self._conn_type = state_dump['conn_type']
self._neighbors = state_dump['neighbors']
self._local_radius = state_dump['local_radius']
self._learn_rate = state_dump['learn_rate']
self._params = state_dump['params']
self._neighbors = None
def __upload_dump_to_python(self, state_dump):
self.__ccore_som_pointer = None
self.__upload_common_part(state_dump)
self._location = state_dump['location']
self._weights = state_dump['weights']
self._award = state_dump['award']
self._capture_objects = state_dump['capture_objects']
self._location = self.__initialize_locations(self._rows, self._cols)
self._create_connections(self._conn_type)
def __upload_dump_to_ccore(self, state_dump):
self.__upload_common_part(state_dump)
self.__ccore_som_pointer = wrapper.som_create(self._rows, self._cols, self._conn_type, self._params)
wrapper.som_load(self.__ccore_som_pointer, state_dump['weights'], state_dump['award'],
state_dump['capture_objects'])
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