AND Gate

# w1, w2는 가중치(weight)를 의미하는 변수입니다.
def AND(x1, x2):
  w1, w2, theta = 0.5, 0.5, 0.7
  tmp = x1*w1 + x2*w2
  if tmp <= theta:
    return 0
  elif tmp > theta:
    return 1

NAND Gate

def  NAND(x1, x2):
  w1, w2, theta = 0.5, 0.5, 0.7
  tmp = x1*w1 + x2*w2
  if tmp <= theta:
    return 1 ## only change here
  elif tmp > theta:
    return 0 ## only change here

OR Gate

def OR(x1, x2):
  w1, w2, theta = 0.5, 0.5, 0.3 ## only change here
  tmp = x1*w1 + x2*w2
  if tmp <= theta:
    return 0 
  elif tmp > theta:
    return 1

XOR Gate

import pandas as pd

index = 0
xor_df = pd.DataFrame()
for i in range(2):
  for j in range(2):
    add_df = pd.DataFrame({'x1' : [i], 'x2' : [j], 'XOR(x1,x2)' : [AND(int(NAND(i, j)), int(OR(i,j)))]}, index = [index])
    xor_df = xor_df.append(add_df)
    index += 1
xor_df