What is the meaning of '...' in help and doc files.

Hi, often in help and documentation I come across descriptions of functions output or input as being (...) or [...]

This is usually when there are several versions of a function call, and I suspect it means 'ditto' but I want to be sure.

eg1: I type 'doc spectrogram'

      S = spectrogram(x)
      S = spectrogram(x,window)
      S = spectrogram(x,window,noverlap)
      S = spectrogram(x,window,noverlap,nfft)
      S = spectrogram(x,window,noverlap,nfft,fs)
      [S,F,T] = spectrogram(x,window,noverlap,F)
      [S,F,T] = spectrogram(x,window,noverlap,F,fs)
      [S,F,T,P] = spectrogram(...)
      spectrogram(...)

Can I interpret the last two lines as:

      [S,F,T,P] = spectrogram(x,window,noverlap,F,fs)
      spectrogram(x,window,noverlap,F,fs)

eg2: I type 'help wavread'

[Y,FS,NBITS]=WAVREAD(FILE) returns the sample rate (FS) in Hertz
    and the number of bits per sample (NBITS) used to encode the
    data in the file.

      [...]=WAVREAD(FILE,N) returns only the first N samples from each
          channel in the file.

      [...]=WAVREAD(FILE,[N1 N2]) returns only samples N1 through N2 from
          each channel in the file.

      [Y,...]=WAVREAD(...,FMT) specifies the data type format of Y used
          to represent samples read from the file.
          If FMT='double', Y contains double-precision normalized samples.
          If FMT='native', Y contains samples in the native data type
          found in the file.  Interpretation of FMT is case-insensitive,
          and partial matching is supported.  If omitted, FMT='double'.

you see, the fourth form of 'wavread' doesn't seem to make sense if '...' means ditto, as 'Y' is already defined in the first form. It could be a simple error in the help though, - the 'doc wavread' is slightly different.

      SIZ=WAVREAD(FILE,'size') returns the size of the audio data contained
          in the file in place of the actual audio data, returning the
          2-element vector SIZ=[samples channels].

      [Y,FS,NBITS,OPTS]=WAVREAD(...) returns a structure OPTS of additional
          information contained in the WAV file.  The content of this
          structure differs from file to file.  Typical structure fields
          include '.fmt' (audio format information) and '.info' (text
          which may describe title, author, etc.)

Thankyou.

Answer 1

[Sean de Wolski]

It is emphasizing that you can receive additional outputs with all of the various combinations of inputs already mentioned.

Answer 2

[Jan]

It is like "[...]" in citations: Something, which does not matter for the currently inspected detail, is left out to improve the readability.