error All arrays must be of same length

This error message in Python is indicating that two or more arrays being used in the same operation have different lengths. For example, when trying to perform mathematical operations such as addition or multiplication, the arrays being used in the operation must have the same number of elements. If they have different lengths, the operation cannot be completed and this error message is raised.

One common situation this error could happen is when working with data in pandas DataFrame, if we have columns with different number of rows, pandas will give you this error.

To resolve this issue, you will need to ensure that all arrays involved in the operation have the same number of elements, by either removing elements from the larger array or adding elements to the smaller array.