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pythonpandasdummy-variable

Iterate through and overwrite specific values in a pandas dataframe

I have a large dataframe collating a bunch of basketball data (screenshot below). Every column to the right of Opp Lineup is a dummy variable indicating if that player (indicated in the column name) is in the current lineup (the last part of the column name is team name, which needs to be compared to the opponent column to make sure two players with the same number and name on different teams don't mess it up). I know several ways of iterating through a pandas dataframe (iterrows, itertuples, iteritems), but I don't know the way to accomplish what I need to, which is for each line in each column:

  1. Compare the team (columnname.split()[2:]) to the Opponent column (except for LSU players)
  2. See if the name (columnname.split()[:2]) is in Opp Lineup or, for LSU players, lineup
  3. If the above conditions are satisfied, replace that value with 1, otherwise leave it as 0

enter image description here

What is the best method for looping through the dataframe and accomplishing this task? Speed doesn't really matter in this instance. I understand all of the logic involved, except I'm not familiar enough with pandas to know how to loop through it, and trying various things I've seen on Google isn't working.

Solution

  • I ended up using a work around. I iterated through using df.iterrows and for each one created a list for each iteration where checked for the value I wanted and then appended the 0 or 1 to the temporary list. Then I simply inserted it to the dataframe. Possibly not the most efficient memory-wise, but it worked.