Creating Variables

[MisterJenn]

Not sure what his error code is showing me. 

error code 

11   data fram_merge;
12   merge fram1_temp fram2_temp;
13   by subjid;
14   age = (vdate-bdate)/365.25;
15   diff_tchol = totchol2 - totchol;
16   if diff_tchol > 1 then ch_tchol > 1;
                            --------
                            180
17   else if diff_tchol < 1 then ch_tchol < 1;
                                 --------
                                 180
ERROR 180-322: Statement is not valid or it is used out of proper order.

18   if diff_tchol = 0 then chtchol = 0;
19   run;

NOTE: The SAS System stopped processing this step because of errors.
WARNING: The data set WORK.FRAM_MERGE may be incomplete.  When this step was stopped there were 0
         observations and 12 variables.
NOTE: DATA statement used (Total process time):
      real time           0.01 seconds
      cpu time            0.01 seconds

proc sort data=fram1_temp; by subjid;
proc sort data=fram2_temp; by subjid; 
data fram_merge;
merge fram1_temp fram2_temp;
by subjid;
age = (vdate-bdate)/365.25;
diff_tchol = totchol2 - totchol;
run;
data fram_merge; 
if diff_tchol > 1 then ch_tchol > 1; 
else if diff_tchol < 1 then ch_tchol < 1;
if diff_tchol = 0 then ch_tchol = 0;
run;

Here is what I am trying to answer

• Create a variable called ch_tchol which equals –, 0, or + depending on whether diff_tchol is negative, zero, or positive in value respectively.

[PaigeMiller]

Logically, I don't even understand what the statement is supposed to be doing, but it is a SAS syntax error.

if diff_tchol > 1 then ch_tchol > 1;

You could do something like this with an equal sign:

if diff_tchol > 1 then ch_tchol = 1;

which avoids the SAS error, but it may not be what you want, and I am not any closer to understanding what you are trying to do logically. Could you explain what the logic is that you are trying to implement in SAS?

[MisterJenn]

Essentially this is what I am trying to do: Create a variable called ch_tchol which equals –, 0, or + depending on whether diff_tchol is negative, zero, or positive in value respectively.

[PaigeMiller]

---

@MisterJenn wrote:
Essentially this is what I am trying to do: Create a variable called ch_tchol which equals –, 0, or + depending on whether diff_tchol is negative, zero, or positive in value respectively.

---

A numeric variable can't have a value of – or +, but it can have values of –1 or +1. So, here you go:

ch_tchol = sign(diff_tchol);

This is different than what you tried to program, in which the cutoffs for diff_tchol was +1, but it is what you just said.

[Kurt_Bremser]

"-" and "+" are not numeric, but character values, so it seems your new variable needs to be of type character.

if diff_tchol > 0
then ch_tchol = "+";
else if diff_tchol = 0
then ch_tchol = "0";
else ch_tchol = "-";

[ballardw]

Personally I wouldn't bother with creating an additional variable after you have the values of diff_tchol.

I would use a custom format to show the values desired.

proc format ;
value sign
low -<0 = '-'
0       = '0'
0 <- High='+'
;
run;

data example;
   input x;
datalines;
-4
.05
0
-.0001
10000000
;

proc print data=example;
   var x;
   format x sign.;
run;

The groups created by a format will be honored by reporting or analysis procedures and most graph procedures.

Also the -, 0, and + would sort in that order. Character values will generally be in a different order and quite often not the one you may want.

Your code also missed any possibility that the difference might be between -1 and 0 or 0 and 1 .

Another reason to consider a format is if you have multiple variables to do this sort of thing with one format can be applied to multiple variables and you do not have to create a separate character value for each. Might be something to consider if you have 50 values that you want to display as -,0,+.