python - GroupBy results to dictionary of lists

Question

I have an excel sheet that looks like so:

Column1 Column2 Column3
0       23      1
1       5       2
1       2       3
1       19      5
2       56      1
2       22      2
3       2       4
3       14      5
4       59      1
5       44      1
5       1       2
5       87      3

And I'm looking to extract that data, group it by column 1, and add it to a dictionary so it appears like this:

{0: [1],
1: [2,3,5],
2: [1,2],
3: [4,5],
4: [1],
5: [1,2,3]}

This is my code so far

excel = pandas.read_excel(r"e:est_data.xlsx", sheetname='mySheet', parse_cols'A,C')
myTable = excel.groupby("Column1").groups
print myTable

However, my output looks like this:

{0: [0L], 1: [1L, 2L, 3L], 2: [4L, 5L], 3: [6L, 7L], 4: [8L], 5: [9L, 10L, 11L]}

Thanks!

Answer 1

You could groupby on Column1 and then take Column3 to apply(list) and call to_dict?

In [81]: df.groupby('Column1')['Column3'].apply(list).to_dict()
Out[81]: {0: [1], 1: [2, 3, 5], 2: [1, 2], 3: [4, 5], 4: [1], 5: [1, 2, 3]}

Or, do

In [433]: {k: list(v) for k, v in df.groupby('Column1')['Column3']}
Out[433]: {0: [1], 1: [2, 3, 5], 2: [1, 2], 3: [4, 5], 4: [1], 5: [1, 2, 3]}