AW: making a block diagonal matrix
- To: mathgroup at smc.vnet.net
- Subject: [mg37573] AW: [mg37548] making a block diagonal matrix
- From: Matthias.Bode at oppenheim.de
- Date: Tue, 5 Nov 2002 05:01:12 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
Hello David,
the following produces your block diagonal matrix:
Needs["LinearAlgebra`MatrixManipulation`"]
Clear[a, b, c, d, e, f, g, h, i, j, k, l, m]
m1 = {{a, b}, {c, d}} // MatrixForm;
m2 = {{e, f, g}, {h, i, j}, {k, l, m}} // MatrixForm;
z1 = ZeroMatrix[2, 3] // MatrixForm;
z2 = ZeroMatrix[3, 2] // MatrixForm;
MatrixForm[AppendColumns[AppendRows[MatrixForm[{{a, b}, {c, d}}],
MatrixForm[{{0, 0, 0}, {0, 0, 0}}]],
AppendRows[MatrixForm[{{0, 0}, {0, 0}, {0, 0}}], MatrixForm[{{e, f, g},
{h, i, j}, {k, l, m}}]]]]
Out1:
MatrixForm[{{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}}]
BTW: Trying to use BlockMatrix[] directly failed; I got the last command
above (the Appends) as output, which upon evaluation - after making it an
*identical* input - yielded the Out1 shown above.
Best regards,
Matthias Bode
Sal. Oppenheim jr. & Cie. KGaA
Koenigsberger Strasse 29
D-60487 Frankfurt am Main
GERMANY
Tel.: +49(0)69 71 34 53 80
Mobile: +49(0)172 6 74 95 77
Fax: +49(0)69 71 34 95 380
E-mail: matthias.bode at oppenheim.de
Internet: http://www.oppenheim.de
-----Ursprüngliche Nachricht-----
Von: David E. Burmaster [mailto:deb at alceon.com]
Gesendet: Montag, 4. November 2002 08:45
An: mathgroup at smc.vnet.net
Betreff: [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
POBox 382069 (new Box number effective 1 Sep 2001)
Harvard Square Station
Cambridge, MA 02238-2069 (new ZIP code effective 1 Sep 2001)
Voice 617-864-4300
Web http://www.Alceon.com
Email deb at Alceon.com
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