[scilab-Users] updating matrix

[Adrien Vogt-Schilb]

Hi

This will show you an example

A=[2 4 6 8 10];
A(3) = []   //deletes the 3rd element of A.


But be aware, if A is very big, this might be very time consuming. (I am 
not sure, thought)
You could prefer something as

B=A //once at the begining

B(3) = %nan  //when the third element should be "deleted"

if you do so beware of comparisons with nans: they always return false!
1==%nan
1>%nan
1<%nan
%nan == %nan



Le 31/05/2011 11:48, Carrico, Paul a écrit :
>
> Dear all
>
> I've the following matrix :
>
> A = [N1 N2 N3 .... Ni .... Nn ]' with n data
>
> In an iterative process, the idea is to decrease the size of the 
> matrix when the wanted value(integer) is found .
>
> i = 1 -> size = n
> i = 2 -> the ith value is removed => size = n-1
> and so on up to n = 1
>
> Is there a relevant way to do it without creating a temporary matrix B 
> -> copying the upper part/lower part of the matrix -> removing A and 
> renaming B in A ..... ?
>
> The aim is both to limit the number of iterations (and to limit the 
> time consuming) and to have a "clean" synthax !
>
> Thanks for any advice
>
> Regards
>
> Paul
>
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*Adrien Vogt-Schilb*

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