How can I use dataframes in different pages

šŸŽˆ Using Streamlit
1

Iā€™ve a project about some datas and I will use Streamlit for it.

I got the datas from Excel (Node Number Coordinates and Members) and Iā€™ve showed them as you can see at the bottom.

However, I want to plot this datas in second page which is called by ā€œFrame Contacsā€ but I couldnā€™t get the dataframes which is located in first page (Nodes)

I 've checked the internet and foun ā€œSession_stateā€ so am I need to use this things or is there any easy way to do it ?

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2

The basic logic is:

# Check if you've already initialized the data
if 'df' not in st.session_state:
    # Get the data if you haven't
    df = pd.read_csv('my_file.csv')
    # Save the data to session state
    st.session_state.df = df

# Retrieve the data from session state
df = st.session_state.df

Session state acts like a dictionary. If you are only loading data based on some user input/action, then you need to tuck that information away in session state before they leave the page e.g.
st.session_state['some key'] = df

On another page, you can get that variable back with
df = st.session_state['some key']

Just be aware that trying to retrieve something from session state that isnā€™t there will cause an error, thatā€™s why itā€™s best practice to check if the key is in session state at the top of page. If itā€™s not appropriate to force a default value for it on some other page, just make sure to handle the error.

if 'some key' not in st.session_state:
    st.warn('Please go back to page 1 and select the data.')
else:
    # The rest of your plotting page
    pass
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