Hello,

Is it possible to bootstrap a matrix X(n,m)?. if so, where can I find the appropriate code?

Thanks

"ons " <bouslama_ons@yahoo.fr> wrote in message <julshf$i9$1@newscl01ah.mathworks.com>...
> Hello,
> 
> Is it possible to bootstrap a matrix X(n,m)?. if so, where can I find the appropriate code?
> 
> Thanks

Please explain 

1. the phrase "bootstrap a matrix".
2. Why you want to do it.

Greg

Thank you Greg,
1- I have a matrix with dimension (n, m), and I need to draw randomly  blocks (with dimension (n1, m1)) of this matrix that belongs to the same time .

2- I whant to do it to perform  optimization using data with dimension (n1, m1)




"Greg Heath" <heath@alumni.brown.edu> wrote in message <jun2gk$5cg$1@newscl01ah.mathworks.com>...
> "ons " <bouslama_ons@yahoo.fr> wrote in message <julshf$i9$1@newscl01ah.mathworks.com>...
> > Hello,
> > 
> > Is it possible to bootstrap a matrix X(n,m)?. if so, where can I find the appropriate code?
> > 
> > Thanks
> 
> Please explain 
> 
> 1. the phrase "bootstrap a matrix".
> 2. Why you want to do it.
> 
> Greg

CORRECTED FOR THE HEINOUS SIN OF TOP-POSTING

"ons " <bouslama_ons@yahoo.fr> wrote in message <juojnf$kvt$1@newscl01ah.mathworks.com>...
> "Greg Heath" <heath@alumni.brown.edu> wrote in message <jun2gk$5cg$1@newscl01ah.mathworks.com>...
> > "ons " <bouslama_ons@yahoo.fr> wrote in message <julshf$i9$1@newscl01ah.mathworks.com>...

> > > Is it possible to bootstrap a matrix X(n,m)?. if so, where can I find the appropriate code?

> > Please explain 
> > 
> > 1. the phrase "bootstrap a matrix".
> > 2. Why you want to do it.

> Thank you Greg,
> 1- I have a matrix with dimension (n, m), and I need to draw randomly  blocks (with dimension (n1, m1)) of this matrix that belongs to the same time .
> 
> 2- I whant to do it to perform  optimization using data with dimension (n1, m1)

Still perplexed.

Nevertheless, the terminology "bootstrap a matrix" seems innappropriate.

Greg

"Greg Heath" <heath@alumni.brown.edu> wrote in message <jvdiep$2jn$1@newscl01ah.mathworks.com>...
> 
> CORRECTED FOR THE HEINOUS SIN OF TOP-POSTING
> 
> "ons " <bouslama_ons@yahoo.fr> wrote in message <juojnf$kvt$1@newscl01ah.mathworks.com>...
> > "Greg Heath" <heath@alumni.brown.edu> wrote in message <jun2gk$5cg$1@newscl01ah.mathworks.com>...
> > > "ons " <bouslama_ons@yahoo.fr> wrote in message <julshf$i9$1@newscl01ah.mathworks.com>...
> 
> > > > Is it possible to bootstrap a matrix X(n,m)?. if so, where can I find the appropriate code?
> 
> > > Please explain 
> > > 
> > > 1. the phrase "bootstrap a matrix".
> > > 2. Why you want to do it.
> 
> > Thank you Greg,
> > 1- I have a matrix with dimension (n, m), and I need to draw randomly  blocks (with dimension (n1, m1)) of this matrix that belongs to the same time .
> > 
> > 2- I whant to do it to perform  optimization using data with dimension (n1, m1)
> 
> Still perplexed.
> 
> Nevertheless, the terminology "bootstrap a matrix" seems innappropriate.

If you want to extract random submatrices, this is one way:

clear all, clc
A = magic(10)
N = 12
k=0
for n = 1:N
    
    k = k+1
    i = round(1+6*rand)
    j = round(1+6*rand)
    
    B{k} = A( i:i+2, j:j+2)
end

Hope this helps.

Greg