Finding the delta (subtraction) of two cells in an existing matrix

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itzhak mal 2019-4-16

评论： Star Strider 2019-4-16

Hi,

I have a matrix with 10^7 rows and 17 columns.

Column number 17 is the time and I want to add another column, 18, that will have the delta of these time steps..

for example:

will yield

I get do loops cause there are 10^7 million rows.. it would take ages. Any ideas? Perhaps a boolian expression would do the trick? Thanks!!!

Star Strider 2019-4-16

Use the diff (link) function, and add a ‘0’ to the output, so the row lengths will be the same:

time = [ 1
         5
        15]
dtime = [0; diff(time)]

producing:

itzhak mal 2019-4-16

thank you!

Star Strider 2019-4-16

As always, my pleasure!

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