Fixed index mismatch issue when passing a dataframe to the sankey function which has been sorted in any way

[minoguep]

Hi there 👋

Two small changes here.

Noticed an issue when using this module the other day where if you pass a dataframe that has been sorted based on the weights, the output is incorrect (see example attached below). I did a bit of digging and I noticed that this is because you reindex left and right if they are passed as a series but not the leftWeight and rightWeight, so when you then create the dataFrame variable, there is in index mismatch and the values get jumbled up basically.

second thing I noticed is that when you check_data_matches_labelson the right hand side, you were actually passing in the leftLabels rather than the rightLabels which I think is incorrect.

Example

Sample dataset

left,right,weight
apple,apple, 2
apple,orange, 3
apple,banana,3
orange,apple,5
orange,orange,7
orange,banana,2
banana,apple,4
banana,orange,1
banana,banana,0

Create Sankey's

import pandas as pd 
from pySankey.sankey import sankey


data = pd.read_csv("sample_data.csv")


# Example 1: No reordering
sankey(
    left=data["left"], right=data["right"], 
    leftWeight=data["weight"], rightWeight=data["weight"], 
    aspect=20, fontsize=20
)


# Example 2: Some sorting applied (notice the difference in banana -> orange, and orange -> orange)
data_sorted = data.sort_values(by="weight")
sankey(
    left=data_sorted["left"], right=data_sorted["right"], 
    leftWeight=data_sorted["weight"], rightWeight=data_sorted["weight"], 
    aspect=20, fontsize=20
)

[Pierre-Sassoulas]

This repo is not maintened or deploying new versions, you can open the PR in my fork if you want.

[minoguep]

Thanks for the heads up, will do that now!