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nframes = params[:4] - vipinv23 - Jan-18-2019
Hello,
I am using the following code in wave file processing:
f = wave.open("file.wav", "rb")
params = f.getparams()
nchannels, sampwidth, framerate, nframes = params[:4]
but i have not understood the working of "nframes = params[:4]"
what does "params[:4]" means?
[:4] is used for what?
Please guide
RE: nframes = params[:4] - johnb546 - Jan-18-2019
If I was to take a guess I would say that it means assign the 4th entry to nframes from the supplied f.getparams. So if you had 1 2 3 4 as the input it would assign 4 to nframes.
Regards
RE: nframes = params[:4] - vipinv23 - Jan-18-2019
Hello,
I have got it
Thank you
RE: nframes = params[:4] - buran - Jan-18-2019
That is slicing notation. It will give you everything from index 0, up to, but not including index 4. in other words - first 4 elements of params.
RE: nframes = params[:4] - perfringo - Jan-18-2019
(Jan-18-2019, 10:22 AM)vipinv23 Wrote: nchannels, sampwidth, framerate, nframes = params[:4]
As buran already answered, it's slicing combined with unpacking.
What it does can be explained with following code:
>>> a = [1, 2, 3, 4, 5] >>> a[:4] [1, 2, 3, 4] >>> one, two, three, four = a[:4] >>> one 1 >>> two 2 >>> three 3 >>> four 4
RE: nframes = params[:4] - vipinv23 - Jan-18-2019
Hello All,
Thank you for your replies.
Now I am able to related to [:4] means