I am trying to combine two dataframes into the second dataframe, but duplicating the first dataframe into every row of dataframe two.
The first dataframe (df1) contains the identifing information, and the other dataframe (df2) contains data about that identifying information. They are in different dataframes since they come from different files. I am sure there is an easy way to do this, but cant seem to find it. The basic problem is there are no unique identifiers on df2 yet, and I need them from df1.
For example, I get df1 from a file containing the identifing information (this dataframe will always only have 1 row, some chance that the column names change as well):
UID Name ID2 0 21YX4 Alan 21458200
while df2 comes from another file, but contains no base identifying information, like this (this dataframe can have very many rows and columns, and columns vary by file). df2's keys in this case are c and d (the index is reset), but that is not the problem, the real ID is in df1:
df2 Out: a b c d e 0 1.427962 NaN shark 0 0.0 1 -0.977258 7.000000 shark 1 NaN 2 -0.301779 NaN python 0 NaN 3 0.393833 NaN panda 1 1.0 4 0.494462 7.0 panda 2 0.0 5 -0.526740 5.000000 shark 2 NaN
UID Name ID2 a b c d e 0 21YX4 Alan 21458200 1.427962 NaN shark 0 0.0 1 21YX4 Alan 21458200 -0.977258 7.000000 shark 0 NaN 2 21YX4 Alan 21458200 -0.301779 NaN python 1 NaN 3 21YX4 Alan 21458200 0.393833 NaN panda 1 1.0 4 21YX4 Alan 21458200 0.494462 7.0 panda 2 0.0 5 21YX4 Alan 21458200 -0.526740 5.000000 shark 2 NaN
I have tried concat, join as well as looping through the keys, but no luck so far. A join like:
puts df1 into df2, but as a new row with no data, and no ID values for the data rows. Is reshape or repeat necessary somehow or is there an easy way to do this?