introduction-to-deep-learning/Le Deep Learning de A a Z/Part 4 - Self_Organizing_Maps/som.py

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1.1 KiB
Python

# Self Organizing Map
# Importing the libraries
import numpy as np
import pandas as pd
# Importing the dataset
dataset = pd.read_csv('Credit_Card_Applications.csv')
X = dataset.iloc[:, :-1].values
y = dataset.iloc[:, -1].values
# Feature Scaling
from sklearn.preprocessing import MinMaxScaler
sc = MinMaxScaler(feature_range = (0, 1))
X = sc.fit_transform(X)
# Training the SOM
from minisom import MiniSom
som = MiniSom(x = 10, y = 10, input_len = 15, sigma = 1.0, learning_rate = 0.5)
som.random_weights_init(X)
som.train_random(data = X, num_iteration = 100)
# Visualizing the results
from pylab import bone, pcolor, colorbar, plot, show
bone()
pcolor(som.distance_map().T)
colorbar()
markers = ['o', 's']
colors = ['r', 'g']
for i, x in enumerate(X):
w = som.winner(x)
plot(w[0] + 0.5,
w[1] + 0.5,
markers[y[i]],
markeredgecolor = colors[y[i]],
markerfacecolor = 'None',
markersize = 10,
markeredgewidth = 2)
show()
# Finding the frauds
mappings = som.win_map(X)
frauds = np.concatenate((mappings[(8,1)], mappings[(6,8)]), axis = 0)
frauds = sc.inverse_transform(frauds)