Filter logic

Using Streamlit
1

Hi everyone, I currently have a view with a dataframe and 5 filters. The problem I have is that I can’t find a way to build a dynamic logic (users have the possibility to only use only 1 filter), and the only way I found is with the ‘if elif’ statement for all the combinations possible (not very convenient).

If there a better way to solve this?

Thanks!

Pierre

1 Like
2

Hi pvtaisne,

See below for an example with multiple filters for one dataframe. Let me know if it helps you :slight_smile:

import streamlit as st
import pandas as pd
import numpy as np

np.random.seed(0)  # Seed so random arrays do not change on each rerun
n_rows = 1000
random_data = pd.DataFrame(
    {"A": np.random.random(size=n_rows), "B": np.random.random(size=n_rows)}
)

sliders = {
    "A": st.sidebar.slider(
        "Filter A", min_value=0.0, max_value=1.0, value=(0.0, 1.0), step=0.01
    ),
    "B": st.sidebar.slider(
        "Filter B", min_value=0.0, max_value=1.0, value=(0.0, 1.0), step=0.01
    ),
}

filter = np.full(n_rows, True)  # Initialize filter as only True

for feature_name, slider in sliders.items():
    # Here we update the filter to take into account the value of each slider
    filter = (
        filter
        & (random_data[feature_name] >= slider[0])
        & (random_data[feature_name] <= slider[1])
    )

st.write(random_data[filter])
3 Likes
3

Thanks Peter, that is what I was looking for :slight_smile:

1 Like
4

Hey Peter,

Thank you for that reply, I was looking for something like that as well.

But could you explain what do you mean by “Initialize filter as onyl true”. I didn’t understand the purpose of this line: filter = np.full(n_rows, True) # Initialize filter as only True

Thanks again!

5

Hi Mariana,

The way the filtering works is that rows which are filtered away are set to false in the filter, and rows which are kept set to true. I initialize the filter to all true which corresponds to “no filter” and then apply filterings one at a time in the for loop. Hope it makes sense…

Best,
Peter

6

@PeterT, you are my saviour. Thanks for this useful tip. I’ve been looking for this solution for weeks. I have seen people asking for help on this issue on StackOverflow and Streamlit and the posts were left unanswered!