St.file_uploader "AttributeError"

Using Streamlit
#1

Hello,

I would want to open an .CSV file with st.file_uploader and return a data frame. My code returns a non type object accompanied with an error message of
" AttributeError: ‘NoneType’ object has no attribute ‘iloc’"

Here is the function that I wrote for this task:

data_file = st.sidebar.file_uploader("Upload ELE.CSV" , type=['csv'])
def upload():
    if data_file is not None:
        df= pd.read_csv(data_file , header=None , sep=';' , encoding='unicode_escape' , skip_blank_lines=False)
        return st.dataframe(df)

ELE = upload()
x0 = np.array(ELE.iloc[0 , 1:142].astype(float))
st.write(x0)

at the output I see the content of the file with the error message:

Untitled
Untitled1014×289 47.4 KB

Could anyone make a suggestion to resolve this issue?
Thank you very much.
Payman

#2

Hi @Payman, welcome to the Streamlit community!

Your issue is here. The thing to keep in mind about st.dataframe is that it is a display object, it does not return a dataframe. You should just return df from your function.

Best,
Randy

1 Like
#3

Thank you very much @randyzwitch for your advice.
There is still one problem, I get the same error message before uploading the file. Once it is uploaded, everything works fine. Could you please let me know how to fix this?

#4

Your code doesn’t work because ELE resolves to None for the function upload() on the first run. Then, you try to run np.array on that None object, which won’t work.

I would move the if data_file: statement outside of the upload() function and place it before the ELE creation line.

Best,
Randy

1 Like
#5

Borrowing the idea from here, the code that worked for me is:

st.sidebar.file_uploader( label="Upload ELE.CSV", accept_multiple_files=False, type=['csv', 'xlsx'], key = "Uploaded File" )

if st.session_state["Uploaded File"] is None:
    st.info("Please upload the ELEVATION file in the sidebar")
    st.stop()
elif st.session_state["Uploaded File"] is not None:
    original_file_name  = st.session_state["Uploaded File"].name
    data_file = st.session_state["Uploaded File"]
st.write('File name: ', data_file.name)
ELE = upload(data_file)