Skip to content
Advertisement

Python: How to find 5 lowest values in data frame column?

I have a data frame that looks something like this:

  ID Ah Am  RAs  Ed Em  DEs   Vmag    U-B    B-V    V-I    e_    e_    e_    e_ _ _ _ _ mb n_ 2MASS
   1 10 42 57.6 -59 47 22.6 18.681         1.105  1.461 0.002       0.103 0.053 2 0 1 2       10425765-5947229
   2 10 42 57.7 -59 44 22.2 18.303                2.764 0.012             0.013 2 0 0 2
   3 10 42 57.7 -59 46 58.0 18.610                1.573 0.038             0.039 2 0 0 2       10425776-5946583
   4 10 42 57.8 -59 47 49.5 12.870         0.764  0.799 0.009       0.009 0.009 3 0 1 3       10425773-5947495
   5 10 42 57.8 -59 44 03.4 18.815         1.072  1.433 0.017       0.110 0.043 2 0 1 2
   6 10 42 57.8 -59 48 29.3 18.697                1.304 0.014             0.019 2 0 0 2       10425778-5948293
   7 10 42 57.8 -59 44 08.5 17.817         1.700  2.384 0.011       0.108 0.013 2 0 1 2       10425786-5944083
   8 10 42 57.9 -59 43 11.1 18.621         0.925  1.322 0.014       0.084 0.014 2 0 1 2
   9 10 42 58.0 -59 41 34.4 16.993         0.998  1.742 0.003       0.027 0.003 3 0 1 3       10425799-5941342
  10 10 42 58.0 -59 49 23.3 16.981         0.656  1.043 0.023       0.034 0.023 3 0 1 3       10425796-5949235
  11 10 42 58.1 -59 48 20.2 17.047         0.926  1.003 0.009       0.034 0.017 3 0 1 3
  12 10 42 58.1 -59 47 51.5 17.535         0.879  1.197 0.008       0.071 0.035 2 0 1 2
  13 10 42 58.2 -59 47 16.9 15.982         0.854  1.146 0.006       0.011 0.008 3 0 1 3       10425820-5947169

I want to get the IDs of the rows with the five lowest Vmag values. Is there a convenient way to achieve this?

Advertisement

Answer

Try df.nsmallest(5, 'Vmag')['ID']

User contributions licensed under: CC BY-SA
6 People found this is helpful
Advertisement