201 Pset question

[hdiamondpollock]

Cool pset question from Ellen: calculate a number of means but only wants to output the biggest 3. Solution: loop through, calculate means, put all in a local, then use extended macro fcn to sort the local and only output first 3 from it.

[matthew-white]

:list sort sorts a macro as a string! E.g.:

. loc list 1 4 9 16
. loc sort : list sort list
. di "`sort'"
1 16 4 9

You could put it in a matrix, but I don't think there's an easy way to sort Stata matrices. You could convert the matrix to a Stata dataset using svmat, or create a dataset along the way using post. Or there's Mata.

[hdiamondpollock]

Thanks @matthew-white - having a discussion on this now. Couldn't you just create a new variable, calculate the means and impute them into separate observations of the new variable. Then just sort the new variables and use, say, explicit subcripting to output top 3? I feel Python might be a better solution here!

[matthew-white]

Yeah, any language that easily allows multiple datasets would probably be better! You could create the new variable as long as there are enough observations. (You could try to find the mean of 100 variables in a dataset with 10 observations, in which case this wouldn't work.)