Merge pandas DataFrame on column of float values

Question

I have two data frames that I am trying to merge.

Dataframe A:

    col1    col2    sub    grade
0   1       34.32   x       a 
1   1       34.32   x          


        

Answer 1

You can use a little hack - multiple float columns by some constant like 100, 1000..., convert column to int, merge and last divide by constant:

N = 100
#thank you koalo for comment
A.col2 = np.round(A.col2*N).astype(int) 
B.col2 = np.round(B.col2*N).astype(int) 
df = pd.merge(A, B, how = 'outer', on = ['col1', 'col2'])
df.col2 = df.col2 / N
print (df)
   col1   col2  sub grade group ID
0     1  34.32    x     a     t  z
1     1  34.32    x     b     t  z
2     1  34.33    y     c     r  z
3     2  10.14    z     b     q  z
4     3  33.01    z     a     q  e
5     1  54.32  NaN   NaN     s  w