Lab 2 Part 2

'''
ЛАБ 2 - ЧАСТЬ 2 
Пример для этапов 7-8

'''
##1
import numpy as np
import matplotlib.pyplot as plt

# Функция уравнения прямой y=a*x+b
def straight_line_equation(a,b,x):
    return a * x + b

# уравнение для решающей функции  dij (x , y )= c*y - b*x-a
def dij_method(c,a,b,point):
    return c * point[1] - a * point[0] - b
 
#Класс 1
class1 = np.array([[0.05, 0.91],
                   [0.14, 0.96],
                   [0.16, 0.9],
                   [0.07, 0.7],
                   [0.2, 0.63]])
#Класс 2
class2 = np.array([[0.49, 0.89],
                   [0.34, 0.81],
                   [0.36, 0.67],
                   [0.47, 0.49],
                   [0.52, 0.53]])
#Класс 3
class3 = np.array([[0.55, 0.4],
                   [0.66, 0.32],
                   [0.74, 0.49],
                   [0.89, 0.3],
                   [0.77, 0.2]])



#Центроиды класса 1 - centroid_сlass1, класса 2 - centroid_сlass2, класса 3 - centroid_сlass3
centroid_сlass1 = np.array([0.125, 0.795])
centroid_сlass2 = np.array([0.43, 0.69])
centroid_сlass3 = np.array([0.72, 0.345])

a12 = 2.9047
b12 = -0.0636
x12 = np.arange(0,0.38,0.01)
y12 = straight_line_equation(a12,b12,x12)
plt.plot(x12,y12)

a13 = 1.3222
b13 = 0.01136
x13 = np.arange(0.1,0.75,0.01)
y13 = straight_line_equation(a13,b13,x13)


a23 = 0.84058
b23 = 0.03417
x23 = np.arange(0.058, 1, 0.01)
y23 = straight_line_equation(a23,b23,x23)

 
# # Коэффициенты уравнения границ между классами c*y-a*x-b=0
params_class1=np.array([[1, a12, b12],[1, a13, b13]])
params_class2=np.array([[1, a12, b12],[1, a23, b23]])
params_class3=np.array([[1, a13, b13],[1, a23, b23]])

## для класса 1
d_C1y12=dij_method(1,a12,b12,centroid_сlass1)
d_C1y13=dij_method(1,a13,b13,centroid_сlass1)

if d_C1y12 < 0:
   params_class1[0,:] =- params_class1[0,:] 
if d_C1y13 < 0:
   params_class1[1,:] =- params_class1[1,:] 

# для класса 2
d_C2y12=dij_method(1, a12, b12, centroid_сlass2)
d_C2y23=dij_method(1, a23, b23, centroid_сlass2)
if d_C2y12 < 0:
   params_class2[0,:] =- params_class2[0,:] 
if d_C2y23 < 0:
   params_class2[1,:] =- params_class2[1,:]

# для класса 3
d_C3y13 = dij_method(1,a13,b13,centroid_сlass3)
d_C3y23 = dij_method(1,a23,b23,centroid_сlass3)
if d_C3y13 < 0:
   params_class3[0,:] =- params_class3[0,:] 
if d_C3y23 < 0:
   params_class3[1,:] =- params_class3[1,:]

# для последовательного разделения классов
x = np.arange(0,1,0.1)
y = np.arange(0,1,0.1)
xy = np.zeros((len(x)*len(y), 2))
ni = 0
for i in range(len(x)):
   for j in range(len(y)):
      ni += 1
      xy[ni:] = [x[i], y[j]]    
points=xy

new_cl1 = class1
new_cl2 = class2
new_cl3 = class3
[nr,nc] = points.shape
for i in range(nr):
   p = points[i,:]
   a = params_class1[0,1]
   b = params_class1[0,2]
   c = params_class1[0,0]

   if dij_method(c,a,b,p) > 0:
      new_cl1 = np.vstack([new_cl1,p])
   else:
      a = params_class2[1,1]
      b = params_class2[1,2]
      c = params_class2[1,0]

      if dij_method(c,a,b,p) > 0:
         new_cl2 = np.vstack([new_cl2,p])
      else:
         new_cl3 = np.vstack([new_cl3,p])
            
         
## Построение рисунка
p1 = plt.plot(new_cl1[:, 0], new_cl1[:, 1], '*r')
p2 = plt.plot(new_cl2[:, 0], new_cl2[:, 1], 'sb')
p3 = plt.plot(new_cl3[:, 0], new_cl3[:, 1], 'om')
plt.plot(x12,y12)
plt.plot(x23,y23)

plt.grid(True)
plt.show()