How to use file name to rename variable

[Tan Nguyen]

Hi all, I have 750 different file(.dta) with same variable is date and Vol, so I need to use the name of this file to rename Vol variable to merge datasets. For example, I want to rename Vol to aaa with automatic ways. I would appreciate any suggestions how can I approach this problem in to-do files.
Thanks for your suggestions.

[Jared Greathouse]

Do you want to merge or append these 750 datasets?

[Tan Nguyen]

I want to merge these 750 datasets. And this image as follow, is the result i want to.

[Jared Greathouse]

Do the original file names all begin with 3 letters?

[Tan Nguyen]

It begins with 3 letters and ".csv". For example: "aaa.csv", "aam.csv",....

[Jared Greathouse]

Here's some syntax to get you started. I haven't tested this, so if I were you I'd experiment with one or two datasets first.

cls


foreach name in .dta {

** Grabs the shapefile data we're interested in
local files : dir "`c(pwd)'" files "*`name'*"

foreach f of loc files { // loop through them all

loc x: di  substr("`f'",1,3)

qui {

u `f', clear

rename Vol `x'

sa `f', replace // ONLY do this if it works

}  // end qui
} // end foreach f
} // end foreach name

What I do here is I loop through your files and grab the first three characters of your file and rename Vol to whatever those first three characters are.

NOTE: if this were my problem, I'd save all of these as tempfiles in the last line and then merge them at the very end to whatever our master dataset is. I also presume these are the only datasets in your current directory