### Code:

import matplotlib.pyplot as plt
import numpy as np
from sklearn import datasets, linear_model
house_price = [245, 312, 279, 308, 199, 219, 405, 324, 319, 255]
size = [1400, 1600, 1700, 1875, 1100, 1550, 2350, 2450, 1425, 1700]
size2 = np.array(size).reshape((-1, 1))
#fitting into the model
regr = linear_model.LinearRegression()
regr.fit(size2, house_price)
print("Coefficients: \n", regr.coef_)
print("intercept: \n", regr.intercept_)
#############################
#formula obtained for the trained model
def graph(formula, x_range):
x = np.array(x_range)
y = eval(formula)
plt.plot(x, y)
#plotting the prediction line
graph('regr.coef_*x + regr.intercept_', range(1000, 2700))
print(regr.score(size2, house_price))
plt.scatter (size,house_price, color='black')
plt.ylabel('house price')
plt.xlabel('size of house')
plt.show()


### Error

**Error Line:print regr.predict([2000])**
Error: File "<ipython-input-4-9afa91ca7f9e>", line 1
print regr.predict([2000])
^
SyntaxError: invalid syntax

• what are you trying to do? – Media Jan 31 '18 at 7:34
• I guess your problem is because of your print line. use print as a function: – Media Jan 31 '18 at 7:35
• @Toros91 I guess it is because he is using python 3.6 – Media Jan 31 '18 at 7:48
• Agreed, he needs brackets for the print. But, there is a much more nefarious problem in his way of using predict. – JahKnows Jan 31 '18 at 7:55
• I was surprised this question got into HNQ with such generic title and code dump... – Andrew T. Jan 31 '18 at 11:03

print regr.predict([2000])


This will not work. The first error is the lack of brackets around the contents of your print statement which is required in Python 3. Change this first to

print(regr.predict([2000]))


However, you will see that this does not work either. I suspect you are attempting to evaluate the price for a new $size = 2000$. You will need to reshape the input to your regression for this to work.

new_size = np.array([2000]).reshape((-1, 1))
print(regr.predict(new_size))


[ 317.78380528]

• +1 I din't know about that bracket thing for python version above 3, nice will remember. – Toros91 Jan 31 '18 at 7:58