topic Re: How to assign the values of the existing variable to a new variable with modification? in SAS Programming

How to assign the values of the existing variable to a new variable with modification?

SAS_John — Thu, 15 Jun 2017 21:44:18 GMT

Hi,

I am writting a program and want to assign the values of the existing variable to a new variable with some modification, but have a problem with it. the new variable VISNUMEN has the missing value. Any help is greatly appreciated. the coding is as the following:

	if VISITNUM=13 and strip(upcase(DSTERM))='PROTCOL COMPLETED' then VISNUMEN=12;
	else if VISITNUM=12 and strip(upcase(DSTERM))='PROTCOL COMPLETED' then VISNUMEN=VISITNUM;

Thanks!

Re: How to assign the values of the existing variable to a new variable with modification?

Reeza — Thu, 15 Jun 2017 21:49:57 GMT

It has all missing values or some missing values? Are you sure all conditions are being capture by your logic?

The easiest way to check something like this is to use a PROC FREQ with the new and old values.

proc freq data=have;
where strip(upcase(dsterm)) = 'PROTOCOL COMPLETED' ;

table visitnum*visnumen;

run;

Re: How to assign the values of the existing variable to a new variable with modification?

kiranv_ — Thu, 15 Jun 2017 21:52:10 GMT

you may need to give a else statement. If you can do not give else statement, then you will get null if scenarious you have mentioned does not cover all the records. you should probably do else varnum = somevalue

Re: How to assign the values of the existing variable to a new variable with modification?

SAS_John — Thu, 15 Jun 2017 21:59:56 GMT

Thanks Reeza for the response. Yes, it is all missing values.

Re: How to assign the values of the existing variable to a new variable with modification?

SAS_John — Thu, 15 Jun 2017 22:02:51 GMT

Here the coding purpose is to change the vaule of '13' for VISITNUM to the vaule of '12' of VISNUMEN. it seems that this did not work

Re: How to assign the values of the existing variable to a new variable with modification?

Reeza — Thu, 15 Jun 2017 22:03:49 GMT

1. What does your log say?

2. What's the type and format of visitnum

Re: How to assign the values of the existing variable to a new variable with modification?

SAS_John — Thu, 15 Jun 2017 22:08:41 GMT

1 OPTIONS NONOTES NOSTIMER NOSOURCE NOSYNTAXCHECK;

56 data ds;

57 set sdtm.ds(rename=(DSDECOD=DSDECOD_ DSTERM=DSTERM_));

59 where strip(upcase(DSCAT))='DISPOSITION EVENT';

61 length DCDECOD $27 DCREASCD $50 DISCONFL DSRAEFL $1 VISNUMEN 8.;

62 DCDECOD=DSDECOD_;

63 DCREASCD=DSTERM_;

65 if strip(upcase(DSDECOD_))^='COMPLETED' then DISCONFL='Y';

66 else DISCONFL='';

68 if strip(upcase(DSDECOD_))='ADVERSE EVENT' then DSRAEFL='Y';

69 else DSRAEFL='';

71 if VISITNUM=13 and strip(upcase(DSTERM))='PROTCOL COMPLETED' then VISNUMEN=12;

72 else if VISITNUM=12 and strip(upcase(DSTERM))='PROTCOL COMPLETED' then VISNUMEN=VISITNUM;

74 keep USUBJID DCDECOD DCREASCD DISCONFL DSRAEFL DSSTDTC VISNUMEN;

75 label DCDECOD='Standardized Disposition Term'

76 DCREASCD='Reason for Discontinuation'

77 DISCONFL='Did the Subject Discontinue the Study?'

78 DSRAEFL='Discontinued due to AE?'

79 VISNUMEN='End of Trt Visit (Vis 12 or Early Term.)'

80 ;

81 run;

NOTE: Numeric values have been converted to character values at the places given by: (Line):(Column).

71:34 72:39

NOTE: Variable DSTERM is uninitialized.

NOTE: There were 306 observations read from the data set SDTM.DS.

WHERE STRIP(UPCASE(DSCAT))='DISPOSITION EVENT';

NOTE: The data set WORK.DS has 306 observations and 7 variables.

NOTE: DATA statement used (Total process time):

real time 0.27 seconds

cpu time 0.23 seconds

Re: How to assign the values of the existing variable to a new variable with modification?

Reeza — Thu, 15 Jun 2017 22:39:00 GMT

Fix these two issues and you'll solve your problem:

NOTE: Numeric values have been converted to character values at the places given by: (Line)Column).

71:34 72:39

NOTE: Variable DSTERM is uninitialized.

VISITNUM is likely character so you should have the values in quotes in the IF.

DSTERM is not a variable in your dataset so your condition is never met, so all values are missing.

Read your log.