Re: a vector of indices of the largest elements in a vector not exceeding the elements of some other vector

[Reimar Bauer <r.bauer(at)fz-juelich.de>]

Derek Hullinger wrote:
> 
> I have two vectors of different sizes (say, A and B):
> 
>         A contains floating point values that increase with index
>         B contains floating point values
> 
> I'd like to create a third vector, C (which would be the same size as
> B) such that:
> 
>         The nth element in C contains the index of the largest element in A
> that does not exceed the nth element in B.
> 
> **
> 
> For example:
> 
> if
> 
> A=[10,20,30,40]
> B=[12,37]
> 
> then
> 
> C=[0,2],
> 
> because the 0th element in A is the largest value in A that does not
> exceed 12, and the 2nd element in A is the largest value in A that
> does not exceed 37.
> 
> **
> 
> I have found a way to do this if B is a single floating point value
> (not a vector of values):
> 
>         temp=max(A<B,C)
> 
> but I haven't been able to find a way to do this with a vector B.  Any
> ideas?

for some reasons value_locate is the best solution but sometimes not

another routine of our library may be useful.

http://www.fz-juelich.de/icg/icg1/idl_icglib/idl_source/idl_work/rb_lib/find_indices_by_window.pro
http://www.fz-juelich.de/icg/icg1/idl_icglib/idl_source/idl_html/dbase/download/find_indices_by_window.tar.gz


The difference to value_locate is that your are able to define a window.

We are using this routine by the time synchronisation for means. 


regards
Reimar

-- 
Reimar Bauer 

Institut fuer Stratosphaerische Chemie (ICG-1)
Forschungszentrum Juelich
email: R.Bauer@fz-juelich.de
http://www.fz-juelich.de/icg/icg1/
==================================================================
a IDL library at ForschungsZentrum Juelich
http://www.fz-juelich.de/icg/icg1/idl_icglib/idl_lib_intro.html

http://www.fz-juelich.de/zb/text/publikation/juel3786.html
==================================================================

read something about linux / windows
http://www.suse.de/de/news/hotnews/MS.html