comp.lang.idl-pvwave archive - RDF feed
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description: Messages from Usenet group comp.lang.idl-pvwave, compiled by Paulo Penteado
items: Re: a matrix whose some elements are matrixes

Re: a matrix whose some elements are matrixes
type: item
description: Here's a small example which should help you: a=[[1,0],[0,1]] b=[[2,2],[2,2]] IDL> print,a 1 0 0 1 IDL> print,b 2 2 2 2 To have a matrix c=[[a,b],[b,a]] do: c=intarr(4,4) c[0,0]=a c[0,2]=b c[2,0]=b c[2,2]=a The output is: IDL> print,c 1 0 2 2 0 1 2 2 2 2 1 0 2 2 0 1 The trick is to figure out where the upper left corners of the smaller matrices fit into the larger matrix you want to build... Ciao, Paolo haojuanchina@gmail.com wrote: > I want obtain a matric whose some elements are matrixes, how to compile > the program? > example: Iwant to abtain the following matrix > G I I I I I 0 > I G I 0 0 0 0 > I I G I 0 0 0 > I 0 I G I 0 0 > I 0 0 I G I 0 > I 0 0 0 I G I > 0 0 0 0 0 I G > in which I is an identity matrix, > 1 0 0 0 0 0 0 > 0 1 0 0 0 0 0 > 0 0 1 0 0 0 0 > 0 0 0 1 0 0 0 > 0 0 0 0 1 0 0 > 0 0 0 0 0 1 0 > 0 0 0 0 0 0 1 > and G is a similar diagonal matrix: > 1 -0.25 -0.25 -0.25 -0.25 -0.25 0 > -0.25 1 0 0 0 0 0 > -0.25 0 1 0 0 0 0 > -0.25 0 0 1 0 0 0 > -0.25 0 0 0 1 0 0 > -0.25 0 0 0 0 1 0 > 0 0 0 0 0 0 1 > I can compile the program of the matrix G: > PRO Matrix > > diag =findgen(7) > sub=findgen(6) > super=findgen(6) > > diag[0:6]=1 > sub[0:5]=-0.25 > super[0:5]=-0.25 > > G = DIAG_MATRIX(diag) + $ > DIAG_MATRIX(super, 1) + DIAG_MATRIX(sub, -1) > G[0,1:5]=-0.25 > G[1:5,0]=-0.25 > print,G > > I= DIAG_MATRIX(diag[0:6]);*(-0.25) > print,I > > END > > but how to get the first matrix in which include the matrix G and I ? > Please give me a help!thanks. >
creator: Paolo Grigis
date: 2006-07-10T09:12:30-00:00