indexing - In PANDAS, how to get the index of a known value? -


if have known value in column, how can index-value? example: 

in [148]: = pd.dataframe(np.arange(10).reshape(5,2),columns=['c1','c2']) in [149]: out[149]:       c1  c2 0   0   1 1   2   3 2   4   5 ........

as know, can value index corresponding it, this.

in [151]: a.ix[0,1]    in [152]: a.c2[0]   in [154]: a.c2.ix[0]   <--  use index out[151]: 1            out[152]: 1         out[154]: 1            <--  value

but how index value?

there might more 1 index map value, make more sense return list:

in [48]: out[48]:     c1  c2 0   0   1 1   2   3 2   4   5 3   6   7 4   8   9  in [49]: a.c1[a.c1 == 8].index.tolist() out[49]: [4]

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