help: pandas and 2d table

jak nospam at please.ty
Sat Apr 13 09:00:35 EDT 2024


Stefan Ram ha scritto:
> jak <nospam at please.ty> wrote or quoted:
>> Would you show me the path, please?
> 
>    I was not able to read xls here, so I used csv instead; Warning:
>    the script will overwrite file "file_20240412201813_tmp_DML.csv"!
> 
> import pandas as pd
> 
> with open( 'file_20240412201813_tmp_DML.csv', 'w' )as out:
>      print( '''obj,foo1,foo2,foo3,foo4,foo5,foo6
> foo1,aa,ab,zz,ad,ae,af
> foo2,ba,bb,bc,bd,zz,bf
> foo3,ca,zz,cc,cd,ce,zz
> foo4,da,db,dc,dd,de,df
> foo5,ea,eb,ec,zz,ee,ef
> foo6,fa,fb,fc,fd,fe,ff''', file=out )
> 
> df = pd.read_csv( 'file_20240412201813_tmp_DML.csv' )
> 
> result = {}
> 
> for rownum, row in df.iterrows():
>      iterator = row.items()
>      _, rowname = next( iterator )
>      for colname, value in iterator:
>          if value not in result: result[ value ]= []
>          result[ value ].append( ( rowname, colname ))
> 
> print( result )
> 

In reality what I wanted to achieve was this:

     what = 'zz'
     result = {what: []}

     for rownum, row in df.iterrows():
         iterator = row.items()
         _, rowname = next(iterator)
         for colname, value in iterator:
             if value == what:
                 result[what] += [(rowname, colname)]
     print(result)

In any case, thank you again for pointing me in the right direction. I
had lost myself looking for a pandas method that would do this in a
single shot or almost.




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