In wsgi_app error in app, loc doesnt work well with dropdownmenus multi=True

Dash Python
1

Hi

I have a dropdown menu with multi for a callback

but this gives errors

X= dff3.loc[:,[drop1]]

what could I use instead? (when I add more than 1 drop, the app stops …

2

Does your drop downs consist of values to search or column names?

Your loc syntax is incorrect also, looks like you are trying iloc.

Depending on your above answer, I would use isin.

Df.loc[df.isin(multi list)]

3

Hi, the first dropdown consist of column names.

1q: the multi list is a list of all the column names?

I’ve tried Df.loc[df.isin(multi list)] and the app breaks …

4

Can you share the error?

5

Can you also share what you are expecting in the output? Do you just want the specified columns of data?

6 
line 1192, in _getitem_axis
    raise ValueError("Cannot index with multidimensional key")
ValueError: Cannot index with multidimensional key
7

Can you also share what you are expecting in the output? Do you just want the specified columns of data?

8

this is the case of study:

I have some data

Ihave to clean that data befero doing operations

to select the data, I have to choose the columns with the multi dropdown1 (and dont know how to do this)

after this I need to clean data with dropna

then comes all the operations (where the other dropdown comes to action)

and after this, it should give a table of results

that table of results its of width dropdown 2 and hight dropdown 1

and I should show the table in the dashboard

9

If all you want is the data and selected columns, then df[drop1] would do that. No need for loc.

If you still get the error, then it would appear you have a 2D dataframe.

I would need a sample of the data to help further.

10

drop1 is a multi … it can be 2d or 90d (here’s where I struggle)

11

Sharing your code would be helpful then.

12

cant do that … sorry … I’ve tried to be as explicit as I could …

my biggest problem is with the multi dropdown selection

dont know how to loc it?

13

Hi, I’ve managed to print a the data in the dashboard … its not in a table … but at least its the correct data … do you know how I could do a table for this (the data is show very ugly)

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image832×218 31.4 KB

the table must be arranged by the drop2 == columns and drop1 == rows
(the solution was to not use the multi= true in the dropbox … a cheap solution but works)