Invalid numeric data error when trying to make a new variable

[joachimg]

I'm trying to make a binary variable (0, 1) from a variable that has 3 levels, and is character. When I try this code - 

data work.cn202103;
set nsf10.cn202103;
if vax_status=. then vstat=.;
if vax_status="No plan to vax" then vstat=1;
if vax_status="Plan to vax" or vax_status="Already vaxxed" then vstat=1;
run;

Or this code - 

data work.cn202103;
set nsf10.cn202103;
if vax_status=. then vstat=.;
else if vax_status="No plan to vax" then vstat=1;
else vstat=1;
run;

I get a TON of error messages like this one -

NOTE: Invalid numeric data, vax_status='Already vaxxed' , at line 209 column 4.

I can't figure out what I'm doing wrong. Let me know if you need more info, and any help is much appreciated. Thanks. 

[PaigeMiller · Accepted solution]

The first time vax_status appears, you are testing to see if it is equal to a dot, and that means vax_status is numeric. The next times you test vax_status, you test to see if it is equal to a character string. Vax_status can't be both numeric and character. It must be one or the other. This can be deduced via looking at PROC CONTENTS, and/or looking at the actual data values for Vax_status.

[joachimg]

Ahhh of course it was something that simple! Thank you so much. I changed the line to if vax_status=" " then vstat=.; Thanks again! 🙂

[PaigeMiller]

@joachimg 

Tip: from now on, use the MISSING function, which works properly on both character and numeric values. You should be able to use it without having to first figure out if the variable is character or numeric.