Octave中如何获取gradientDescent函数的错误行号？

Absolutely! There are simple, reliable ways to track down the exact line in gradientDescent.m where this dimension mismatch is occurring. Here’s what you can do:

• Use MATLAB’s built-in debugger (easiest method)
  Open your MATLAB command window and run this command first:

  dbstop if error
  

  Then re-run your code as usual. When the nonconformant arguments error hits, MATLAB will automatically pause execution, highlight the exact line in gradientDescent.m that caused the issue, and print the line number in the command window. You can inspect variable dimensions right there to figure out why the matrix product is failing (side note: a 1x97 matrix multiplied by a 97x2 matrix should work for standard matrix multiplication—double-check if you accidentally used element-wise multiplication .* instead of *!).

• Add a try-catch block to log the line number
  If you want to programmatically capture the line number without using the debugger, wrap your function code (or the call to gradientDescent) in a try-catch block:

  try
      % Your existing code that calls gradientDescent, or the full gradientDescent function code
  catch ME
      % Print error details including line number
      fprintf('Error in %s at line %d: %s\n', ME.stack(1).name, ME.stack(1).line, ME.message);
      % Re-throw the error to keep the original behavior
      rethrow(ME);
  end
  

  The ME (error object) contains a stack property that holds the exact line number and function name where the error originated.

• Manually scan for matrix operations
  Since the error is about a matrix product mismatch, you can also quickly scan gradientDescent.m for any * or .* operations. Look for places where you’re multiplying two matrices—compare their dimensions at that line to see which pair is 1x97 and 97x2 (and confirm if the multiplication type makes sense for those shapes).

内容的提问来源于stack exchange，提问作者Script Kitty