Valueerror: x and y must be the same size ( Solved )

You get Valueerror in python when you are giving an invalid value to the function of the correct type. If you are getting Valueerror: x and y must be the same size then it must be due to size mismatch. In this entire tutorial, you will know how to solve this Valueerror: x and y must be the same size in a simple way.

What is ValueError?

Valueerror inherits from the Exception. Most of the time you get this error when there is an invalid type or value passed to the functions. You can continue the remaining code if you wrap the entire code blocks with the try and except statement.

Why Valueerror: x and y must be the same size Comes

The root cause for the Valueerror: x and y must be the same size is passing the arguments to the functions that are of different sizes. The python interpreter tells you that you have passed the value to the functions of different sizes.

Suppose I have a NumPy array x and y of different lengths. The array x contains 5 elements and the array y contains 4 elements. And If I will use both x and y to plot a scatter plot in matplotlib then I will get the ValueError.

You will get the error when you will run the below lines of code.

import numpy as np
import matplotlib.pyplot as plt

x = np.array([10,20,30,40,50])
y = np.arange(1,5)
plt.scatter(x=x,y=y)
plt.show()

Output

Valueerror x and y must be the same size error — Valueerror

Solution for Valueerror: x and y must be the same size

It’s obvious that you will get the error when you are passing the mismatched size for the value. Therefore the solution to this error is very simple. You have to make sure that the size or dimension of the input values should be the same. Take the above example, you have to pass the x and y variables of the same size. It means if x is of size 4 then y size should be 4.

Now if you run the below lines of code then you will not get the error.

import numpy as np
import matplotlib.pyplot as plt

x = np.array([10,20,30,40])
y = np.arange(1,5)
plt.scatter(x=x,y=y)
plt.show()

Output

Scatter Plot for the variable x and y — Scatter Plot for the variables x and y

Conclusion

The exception Valueerror: x and y must be the same size will occur when you are passing the arguments to the function of different sizes. You will not get the error if the size of x and y is the same. The above method will solve your error. Please read the below article for similar errors.