Python
import matplotlib.pyplot as plt
import numpy as np
X=np.array([1,2,4,6,7,8,10,11,13,14,18])
y=np.array([2,4,7,8,10,12,13,15,16,17,19])
print(X,'\n',y)
from sklearn.model_selection import train_test_split
X_train,X_test,y_train,y_test=train_test_split(X,y,test_size=0.30,random_state=1)
print(X_train)
print(y_train)
X_train_mean=np.mean(X_train)
print(X_train_mean)
y_train_mean=np.mean(y_train)
print(y_train_mean)

num1=0
den1=0
for i in range(len(X_train)):
    num1+=(X_train[i]-X_train_mean)*(y_train[i]-y_train_mean)
    den1+=(X_train[i]-X_train_mean)**2
    
b1=num1/den1

print('The slope is ',b1)

b0=y_train_mean-(b1*X_train_mean)

print('The intercept is ',b0)

for i in range(len(X_train)):
    y_predict[i]=
    y_predict[i]=b0+(b1*X_train[i])
    print(X_train[i],' predicts ',y_predict[i])
[ 1  2  4  6  7  8 10 11 13 14 18] 
 [ 2  4  7  8 10 12 13 15 16 17 19]
[ 2 10  1 11 18 13  8]
[ 4 13  2 15 19 16 12]
9.0
11.571428571428571
The slope is  1.027777777777778
The intercept is  2.3214285714285694

line 30, in <module>
    y_predict[i]=0.0
    ~~~~~~~~~^^^
TypeError: 'int' object does not support item assignment