Re: Adding to matrices in mat file

"Steve Hall" <cosmicfish@xxxxxxxx> wrote in message <gpr1f9$hqt$1@xxxxxxxxxxxxxxxxxx>...
Question: Is it possible to sequentially append values to a vector or matrix in a mat file, without opening said mat file?

Example:

a=[1 2 3 4 5]
save 'afile.mat' a

a=6 or a(6)=6 as needed

somehowappendthisthing('afile.mat',a)

load 'afile.mat'

a=[1 2 3 4 5 6]



Any ideas? Holding the whole matrix in memory while doing the computation is dragging things down but I need the data at the end.

I doubt you can't append anything to any file without opening the file.
But if you mean append without reading the contents of the file, then if you only need a simple array you could write it to a binary file. There you can add stuff without reading the existing content.
doc fopen
doc fwrite
.

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