Texas Instruments TI-89 사용자 설명서

Programming

 636

Debugging Techniques

Debugging Techniques

Debugging Techniques

Debugging Techniques

Run-time error messages can locate syntax errors but not errors in program logic. The 
following techniques may be useful.

•

During testing, do not use local variables so that you can check the variable values 
after the program stops. When the program is debugged, declare the applicable 
variables as local.

•

Within a program, temporarily insert 

 and 

 commands to display the 

values of critical variables.

-

 and 

 cannot be used in a user-defined function. To temporarily 

change the function into a program, change 

 and 

 to 

 and 

. Use 

 and 

 to debug the program. Then remove 

 and 

 and change the program back into a function.

•

To confirm that a loop is executed the correct number of times, display the counter 
variable or the values in the conditional test.

•

To confirm that a subroutine is executed, display messages such as 

Entering 

subroutine

 and 

Exiting subroutine

 at the beginning and end of the subroutine.

Error-Handling Commands

Error-Handling Commands

Error-Handling Commands

Error-Handling Commands

Defines a program block that lets the program execute a 
command and, if necessary, recover from an error 
generated by that command.

Clears the error status and sets the error number in system 
variable Errornum to zero.

Passes an error to the next level of the Try...EndTry block.