Re: MATLAB / Octave compatability, spacing, parsing

[John W. Eaton]

On 27-Oct-2005, Steve C. Thompson wrote:

| MATLAB doesn't allow whitespace before the transpose
| operator.
| 
|   [0 1]'
| 
| works in MATLAB, but
| 
|   [0 1] '
| 
| doesn't.  Octave properly parses both cases.

This is odd.  The error is

  >> [0 1] '
  ??? [0 1] '
            |
  Error: A MATLAB string constant is not terminated properly.

but

  >> [0 1] 'x'
  ??? [0 1] 'x'
            |
  Error: Unexpected MATLAB expression.

so why should this use of a single quote character be misinterpreted
as the start of a character string?

Maybe this is related to the stupid kluge for command-style functions,
in which Matlab determines which way to parse something like

  f + x

based on whitespace?  For example, try the following function

  function y = f (varargin)
    varargin{:}
    y = 1

and

  f + 1
  f+ 1
  f +1

At least now they allow f() to force the function to be called without
any arguments.

| MATLAB always requires `...'.
| 
|   rand (1, ...
|         2)
| 
| and
|   
|   rand (1,
|         2)
| 
| both work in Octave.  MATLAB chokes on the later.

Setting "warn_matlab_incompatible = true" in Octave will catch this one.

| Also, something else. MATLAB doesn't support `printf'.
| 
|   foo = 5; 
|   printf('My result is: %d\n', foo)
| 
| works in Octave, but not MATLAB.  If using MATLAB, the kludge
| is to issue `fprintf' instead:
| 
|   foo = 5; 
|   fprintf('My result is: %d\n', foo)

And of course Octave's fprintf is also equivalent to printf if the
first argument happens to be a character string.  Octave has printf
because it somehow seems wrong to me to use an f* function when there
is no file ID argument.

jwe



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