Recent content by patiobarbecue

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    Why Am I Getting an Undefined Function Error for 'double' in QR Factorization?

    I have identical problem on MATLAB 7.10.0 (R2010a): Q = 0.4472 0 0 0 0 0.4472 1.0000 0 0 0 0.4472 0 1.0000 0 0 0.4472 0 0 1.0000 0 0.4472 0...
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    What Matrix is This? References for Structured Matrix

    By rearrange rows of B, I got P, and M=P'*P seems to have a nice pattern, M is singular though. Is it obvious why it is singular? # Created by Octave 3.2.3, Sat Jul 17 18:31:46 2010 EDT # name: M # type: matrix # rows: 8 # columns: 8 9 0 3 3 3 3 3 3 0 9 3 3 3 3 3 3 3 3 6 0 0 2 2 2...
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    What Matrix is This? References for Structured Matrix

    Homework Statement Are there references of the following structured matrix? A = 1 0 1 0 0 1 0 0 1 0 1 0 0 0 1 0 1 1 0 0 0 1 0 1 0 0 1 0 0 1 ; Say we have group A=1,2; group B=1,2, 3; the rows of above matrix shows all possible selections: one element from each group. Hence A...
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    Notation for third order derivative of a vector function

    my textbook never talks about linear form, bilinear or trilinear form. please give me a good reference. thanks.
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    Notation for third order derivative of a vector function

    1. let f: R^n -> R, then f' is a vector and f'' is a matrix, how about f'''? it is a cube? I guess we have to use matrix notation for f'''. I have seen the notation " f'''(x)(h,h,h) ", which is a real number for sure. I have no clue how to operate it though. Any reference on third order...
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    ? p-norm <= (p-1)norm <= <= 2-norm <= 1-norm?

    1. the p-norm for a vector x in R^n is defined usually: || x ||_p = (x_1^p + x_2^p + ... + x_n^p)^{1/p} the question is to verify: || x ||_p <= || x ||_{p-1} Homework Equations I guess even more generally p-norm is a decreasing function in p for "any" x? The...
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    Programming libraries for C linear algebra

    Hey, guys, I installed CLAPACK on my Mac without much trouble. However it failes on solving this simple equation Ax = b, where A is singular, yet the routine dgesv_() didn't detect it. Can you test the case on you machine? Here is the input. Matrix: -10.0 -5.0 6.0 3.0 Vector: 0...
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