#!/usr/bin/env python
# coding: utf-8

# In[1]:


# LDA
import numpy as np
import matplotlib.pyplot as plt
import pandas as pd
get_ipython().run_line_magic('matplotlib', 'inline')


# In[2]:


# Veri Seti
url='https://raw.githubusercontent.com/cagriemreakin/Machine-Learning/master/4%20-%20Dimensionality%20Reduction/2%20-%20Linear%20Discriminant%20Analysis/Wine.csv'
dataset = pd.read_csv(url)
X = dataset.iloc[:, 0:13].values
y = dataset.iloc[:, 13].values

# Boyut Sayısı
size=X.shape[1]


# In[3]:


# Eğitim ve Test Set Görselleştirme için Kullanılacak
def visualize(X,y,title):
    from matplotlib.colors import ListedColormap
    plt.figure(figsize=(12,7))
    X_set, y_set = X, y
    X1, X2 = np.meshgrid(np.arange(start = X_set[:, 0].min() - 1, stop = X_set[:, 0].max() + 1, step = 0.01),
                         np.arange(start = X_set[:, 1].min() - 1, stop = X_set[:, 1].max() + 1, step = 0.01))
    plt.contourf(X1, X2, classifier.predict(np.array([X1.ravel(), X2.ravel()]).T).reshape(X1.shape),
                 alpha = 0.75, cmap = ListedColormap(('red', 'green', 'blue')))
    plt.xlim(X1.min(), X1.max())
    plt.ylim(X2.min(), X2.max())
    for i, j in enumerate(np.unique(y_set)):
        plt.scatter(X_set[y_set == j, 0], X_set[y_set == j, 1],
                    c = ListedColormap(('red', 'green', 'blue'))(i), label = j)
    plt.title('Logistic Regression ' + title)
    plt.xlabel('PC1')
    plt.ylabel('PC2')
    plt.legend()
    plt.show()


# In[4]:


# Eğitim ve Test Setine Ayırma
from sklearn.model_selection import train_test_split
X_train, X_test, y_train, y_test = train_test_split(X, y, test_size = 0.2, random_state = 0)


# In[5]:


# Feature Scaling
from sklearn.preprocessing import StandardScaler
sc = StandardScaler()
X_train = sc.fit_transform(X_train)
X_test = sc.transform(X_test)


# In[6]:


#Component sayısına karar verebilmek için n_components' a parametre olarak None değerini atıyoruz.
#Böylece veri setimizdeki explained variance ve cumulative variance değerlerini bulup grafikte gösteriyoruz.
from sklearn.discriminant_analysis import LinearDiscriminantAnalysis 
lda = LinearDiscriminantAnalysis(n_components = 2)
X_train = lda.fit_transform(X_train, y_train)
X_test = lda.transform(X_test)


# In[7]:


# Logistic Regression Modeli ile Veri Setini Eğitme
from sklearn.linear_model import LogisticRegression
classifier = LogisticRegression(random_state = 0)
classifier.fit(X_train, y_train)


# In[8]:


# Sonuçların Tahmini
y_pred = classifier.predict(X_test)


# In[9]:


# Confusion Matrix
from sklearn.metrics import confusion_matrix
cm1 = confusion_matrix(y_test, y_pred)


# In[10]:


print("\n Confusion Matrix for 2 Component\n",cm1)


# In[11]:


from sklearn.metrics import accuracy_score
print("n_components = 2 -> Prediciton: %",accuracy_score(y_pred,y_test)*100)


# In[12]:


visualize(X_train,y_train,'Training Set for 2 Components')
visualize(X_test,y_test,'Test Set for 2 Components')