Removing sets of string characters

[Nick Richardson]

Hello,

I have a string variable (positiveassays) that contains a list of drugs and the levels of drugs detected in the specimen. I am trying to separate out the drug types into separate variables and remove the parentheses and the numeric values within the parentheses as well. Here is a sample of the cases i am working with:

* Example generated by -dataex-. For more info, type help dataex
clear
input str544 positiveassays
"Hydrocodone (388.264)"                                              
"Methamphetamine (246.86)"                                           
"Amphetamine (1600)"                                                 
"Cocaine (800), Benzoylecgonine (800)"                               
"THC (10.96)"                                                        
"Methamphetamine (1600), Hydrocodone (29.156), Amphetamine (116.379)"
"Methamphetamine (242.75)"                                           
"Codeine (275.445), Morphine (800), 6-MAM  (40)"                     
"Cocaine (564.218)"                                                  
"Methamphetamine (249.92)"                                           
end

I tried

split positiveassays, parse(,) gen(drug)

and then

replace drug1 = subinstr(drug1, "(*)", "", .)

But that didnt work. I was trying to remove the parentheses and everything in them.

Any help would be greatly appreciated as always!

[Clyde Schechter]

The people who really understand regular expressions can undoubtedly come up with a shorter solution, but this will do it:

replace positiveassays = ustrregexra(positiveassays, "\(\d*\.\d*\)", "")
replace positiveassays = ustrregexra(positiveassays, "\(\d*\)", "")
split positiveassays, parse(,) gen(drug)

[Nick Richardson]

Thanks so much, Clyde (as usual)! This is exactly what i was looking to do.