[R] Statemement by recurrence avoiding loop

[tlorino@vet-alfort.fr]

Dear R users,

I would like to calculate a cumulative sum as following: on the i-th row, in the
j-th column of a matrix, I would like to obtain the sum of the (i-1) preceding elements of
this j-th column.
Could I avoid a "for" loop?

Thank you,
Tristan Lorino

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Tél. 01 43 96 70 33
Mél. tlorino at vet-alfort.fr
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