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Pandas dataframe - change values ​​based on column header

I have dataframeone that looks like this:

In [74]: data2

Out[74]: 
            a  b  c

2012-06-12  0  1  1
2012-06-13  1  1  0
2012-06-14  1  0  1
2012-06-15  1  0  1
2012-06-16  1  1  0
2012-06-17  1  0  1

Is there a way to make the values ​​= column header, where value = 1?

Result of df:

            a  b  c

2012-06-12  0  b  c
2012-06-13  a  b  0
2012-06-14  a  0  c
2012-06-15  a  0  c
2012-06-16  a  b  0
2012-06-17  a  0  c

And then delete the values ​​that = 0, so that df comes down to two columns: (the column heading doesn't matter at this stage)

Result of df:

            1  2  
2012-06-12  c  b  
2012-06-13  a  b  
2012-06-14  a  c  
2012-06-15  a  c  
2012-06-16  a  b  
2012-06-17  a  c
+5
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2 answers
from pandas import *
df = DataFrame([[0, 1, 1], [1, 1, 0], [1, 0, 1],], columns=['a','b','c'])

foo = []
for i in df.index:
    foo.append( df.columns[df.ix[i] == 1])
DataFrame(foo, index = df.index)

What returns:

   0  1
0  b  c
1  a  b
2  a  c
+5
source

You can also call deeper pandas -fu and do:

In [28]: df.apply(lambda x: x.astype(object).replace(1, x.name))
Out[28]: 
            a  b  c
2012-06-12  0  b  c
2012-06-13  a  b  0
2012-06-14  a  0  c
2012-06-15  a  0  c
2012-06-16  a  b  0
2012-06-17  a  0  c
+6
source

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