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Old   September 13, 2000, 10:07
Default Numerical methods
  #1
Lex
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Hi everybody Developing my code for solving cfd problem I had to make some interpolation of another numerical experiment data So after some time I found some procedures for interpolation by spline good enough for my purposes The only problem is that I'm usin C++ and have no good mathematical libraies So when I had to make the inverse matrix I understood that the time came to find something So I got the linalg packeg from netlib to work with matricies and vectors Looking at the code I understood that it's not bad But now I have trubles with compiling it If anyone used this lib please answer me.
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Old   September 13, 2000, 22:35
Default Re: Numerical methods
  #2
Istadi
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Please use MATLAB . In Matlab, the any interpolation methods and matrix operations have been available.
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Old   September 14, 2000, 04:52
Default Re: MATLAB
  #3
Lex
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Using MATLAB is not a bad idea I often use it for simple purposes But for these time I have to use interpolation in my own solver written in C (C++) so it's to tuff to my mind to use any part of MATLAB in this case
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Old   September 14, 2000, 06:39
Default Re: Numerical methods
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Sebastien Perron
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Is it an obligation to make to inverse matrix?

Wouldn't it be better to solve the system?

If so try templates from netlib. I used it and had no difficulties compiling it.

P.S. As far as I can remember, it is very time consuming to actually calculate the inverse of a matrix.
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Old   September 14, 2000, 09:45
Default Re: MATLAB
  #5
Kai Kang
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Take a look at the numerical receipt, it should at least has some information about matrix operation in Fortran, which is not difficult to convert to C++

Inverse big matrix costs too much of computational effort, why not try iteratively solve it...
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Old   September 15, 2000, 08:48
Default Re: Numerical methods
  #6
Hans Klaufus
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Hi Lex,

I developped some codes (C++) myself for splining, matrix stuff, etc. If you're interested, please send me an email, so I can attach these sources in a replying email.

Cheers, Hans.
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Old   September 17, 2000, 12:16
Default Re: Inverse
  #7
Lex
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Hi

Sometimes it's easier to invert matrix espesially if you have to solve several linear systems with the same matrix but different right parts

Aleksei Privalov
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Old   September 19, 2000, 09:46
Default Re: Numerical methods
  #8
Reza Besharati
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Hi Dear Alex Take a look at the MathLink feature of Mathematica version 4.0,at the addreess: www.wolfram.com I don't know but I think it mught be helpfull. Reza
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