How to subset over indexes in pandas using lambdas

Question

I have the following data sets

df1

f1 f2 f3
1  5  9
2  4  7
3  8  6

These values are indexes for a second df2

df2 - Expected result
index value1 value2 value3
1     0.2     0.2    0.1
2     0.5     0.7    0.8
3     0.4     0.2    0.1
4     0.3     0.1    0.3
5     0.1     0.4    0.1

Edit : I want to run a lambda function over each row of df1 to get a result like df2. As the number of rows and columns is very large, I don't want to use 'for each' type statements. Basically need an efficient way to iterate over df1.

Answer 1

You may check with replace after you get the columns and index match

df2 = df2.set_index('index')
df2.columns = df1.columns
out = df1.replace(df2)
Out[105]: 
    f1   f2  f3
0  0.2  0.4   9
1  0.5  0.1   7
2  0.4  8.0   6