RE: making a block diagonal matrix
- To: mathgroup at smc.vnet.net
 - Subject: [mg37577] RE: [mg37548] making a block diagonal matrix
 - From: "DrBob" <drbob at bigfoot.com>
 - Date: Tue, 5 Nov 2002 05:01:33 -0500 (EST)
 - Reply-to: <drbob at bigfoot.com>
 - Sender: owner-wri-mathgroup at wolfram.com
 
Here's an example.
<< LinearAlgebra`MatrixManipulation`
MatrixForm[blocks = #IdentityMatrix[#] - 2 & /@ {2, 3, 1}]
glue1 = BlockMatrix@{{#1, Table[0, {Length@#1}, {Length@#2}]}, {Table[0,
{
      Length@#2}, {Length@#1}], #2}} &;
MatrixForm[glueAll = Fold[glue1, First@blocks, Rest@blocks]]
DrBob
-----Original Message-----
From: David E. Burmaster [mailto:deb at alceon.com] 
To: mathgroup at smc.vnet.net
Subject: [mg37577] [mg37548] making a block diagonal matrix
Dear MathGroup
Can anyone please suggest an efficient way to convert a list of square
matrices (of different dimensions) into a block diagonal matrix?? The
elements of each matrix are all real numbers
here is an example with a list of two square matrices --
matrix1 =	a b
		c d
matrix2 =	e f g
		h i j
		k l m
output = 	a b 0 0 0
		c d 0 0 0
		0 0 e f g
		0 0 h i j
		0 0 k l m
=-=
many thanks
dave
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David E. Burmaster, Ph.D.
Alceon Corporation
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Email	deb at Alceon.com
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