debug.sas

* Data set debug option is used for programm debugging ;
* this an interactive session the enable programmer to ;
* to discover logic errors - errors the produce unexpected results ;
* Add the data set debugging by using the debug option ;

data numtt / debug;
    set sashelp.class;
    if sex="F" then classHeight = Height - mean(Height);
    else if sex="M" then classHeight = Height - medium(Height);
    else classHeight is missing;
run;


* Debugger commands ;
/*
BREAK	    JUMP
CALCULATE	LIST
DELETE	    QUIT
DESCRIBE	SET
ENTER	    STEP
EXAMINE	    SWAP
GO	        TRACE
HELP	    WATCH
*/


* Break is used to set breakpoints, short form is b ;
b 7 ; * breakpoint at line 7;
b 15 after 4 ; * breakpoint at line 15 after every 4 execution of the line;


* Calculate used to Calculation involving numeric values, short form calc ;
calc income+expense
calc (payment + tax) * rate 



* Delete removes a breakpoint or watch, short form d ;
d b 7;
d w abc;
d b _ALL_ ;



* Describe display the attribute of a variable, short form desc;
desc gender;
desc array{i+k};
desc treatment;



* Examine display the values of variables. short form ex ;
ex _ALL_;
ex n name
ex trt_date date10.


* List displays all occurances of items listed in the argument, short form l ;
l _ALL_;
l w b ;


* Go resume the execution of the program, short form g ;
* With argument, it indicate stop line ;
g ;
g 15 ; * go and stop at line 15 ;


* Step, execute one statement at a time, use ENTER also ;
* with argument, indicate number of statements to execute ;
step ;
step 5 ;


* Jump restarts suspended program ;
* with argument, start at the line or label;
j 45;


* Watch suspend execution when the value of specified variable change, alias w;
w orange;
w income;
w salary