MATLAB Programming

12 Programming Tips
Setting Breakpoints from the Command Line
You can set breakpoints with dbstop in any of the following ways:
• Break at a specific M-file line number.
• Break at the beginning of a specific subfunction.
• BreakatthefirstexecutablelineinanM-file.
• Break when a warning, or error, is generated.
• Break if any infinite or NaN values are encountered.
For more information: See Setting Breakpoints in the MATLAB Desktop
Tools and Development Environment documentation.
Finding Line Numbers to Set Breakpoints
When debugging from the command line, a quick way to find line numbers for
setting breakpoints is to use dbtype. Thedbtype function displays all or part
of an M-file, also numbering each line. To display delaunay.m, use
dbtype delaunay
Todisplayonlylines35through41,use
dbtype delaunay 35:41
Stopping Execution on an Error or Warning
Use dbstop if error to stop program execution on any error and enter
debug mode. Use warning debug to stop execution on any warning and enter
debug mode.
For more information: See Debug, Backtrace, and Verbose Modes in the
MATLAB Programming documentation.
Locating an Error from the Error Message
Click on the underlined text in an error message, and MATLAB opens the
M-file being executed in its editor and places the cursor at the point of error.
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