Grouping data by value ranges

Question

I have a csv file that shows parts on order. The columns include days late, qty and commodity.

I need to group the data by days late and commodity with a sum of the qty.

Answer 1

I know this is coming a bit late, but I had the same problem as you and wanted to share the function np.digitize. It sounds like exactly what you want.

a = np.random.randint(0, 100, 50)
grps = np.arange(0, 100, 10)
grps2 = [1, 20, 25, 40]
print a
[35 76 83 62 57 50 24  0 14 40 21  3 45 30 79 32 29 80 90 38  2 77 50 73 51
 71 29 53 76 16 93 46 14 32 44 77 24 95 48 23 26 49 32 15  2 33 17 88 26 17]

print np.digitize(a, grps)
[ 4  8  9  7  6  6  3  1  2  5  3  1  5  4  8  4  3  9 10  4  1  8  6  8  6
  8  3  6  8  2 10  5  2  4  5  8  3 10  5  3  3  5  4  2  1  4  2  9  3  2]

print np.digitize(a, grps2)
[3 4 4 4 4 4 2 0 1 4 2 1 4 3 4 3 3 4 4 3 1 4 4 4 4 4 3 4 4 1 4 4 1 3 4 4 2
 4 4 2 3 4 3 1 1 3 1 4 3 1]