Rank: 53 based on 2447 downloads (last 30 days) and 21 files submitted

James Tursa

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Lat/Long: 47.68167, -122.2075

Personal Profile:: Interested in external applications, mex & engine applications with Fortran, C, C++, etc.
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Files

Files Posted by James				View all 1 - 5 of 21
Updated	File	Tags	Downloads (last 30 days)	Comments	Rating
11 Nov 2009	mpower2 - A faster matrix power function. mpower2 evaluates matrix to an integer power faster than the MATLAB built-in function mpower. Author: James Tursa	matrix, power, mpower	51	2
11 Nov 2009	polyvalm2 - A faster matrix polynomial evaluator polyvalm2 evaluates a polynomial with a matrix argument faster than the MATLAB function polyvalm. Author: James Tursa	matrix, polynomial, polyvalm, mpower	36	3	5.0 5.0 \| 1 rating
23 Oct 2009	num2vpi - Converts input exactly into vpi Converts double inputs larger than 2^53-1, or char inputs with exponents, exactly into vpi. Author: James Tursa	vpi, precision, variable, integer	109	0
25 Sep 2009	Fortran mex routine mxGetClassName A drop-in replacement for the TMW Fortran API function mxGetClassName routine that does not work. Author: James Tursa	fortran, mxgetclassname, mex, class name	113	0
05 Aug 2009	num2strexact (exact version of num2str) num2strexact does exact conversion of number to string based on IEEE floating point bit pattern Author: James Tursa	num2strexact, str2num, sprintf, num2str, precision, printf	139	0

Comments and Ratings by James		View all 1 - 5 of 19
Updated	File	Comments	Rating
21 Nov 2009	IEEE 754r Half Precision floating point converter Converts MATLAB or C variables to/from IEEE 754r Half Precision floating point bit pattern. Author: James Tursa	Also this: #include <stdint.h>
21 Nov 2009	IEEE 754r Half Precision floating point converter Converts MATLAB or C variables to/from IEEE 754r Half Precision floating point bit pattern. Author: James Tursa	I just got a report from a 64-bit linux user that the ieehalfprecision.c code did not work as posted, but he did get it to work by changing some types as follows: #define INT16_TYPE int16_t #define UINT16_TYPE uint16_t #define INT32_TYPE int32_t #define UINT32_TYPE uint32_t I do not have a 64-bit system to test with, but I would assume this works as long as your compiler supports the int16_t etc types.
12 Nov 2009	mpower2 - A faster matrix power function. mpower2 evaluates matrix to an integer power faster than the MATLAB built-in function mpower. Author: James Tursa	Gianni: Raising to a power with matrix multiplies is not mathematically defined for non-square matrices. Hence mpower2 (and MATLAB's own mpower) do not support this operation. For vectors, an operation that is supported in MATLAB is the element-wise power using the .^ operator.
11 Nov 2009	polyvalm2 - A faster matrix polynomial evaluator polyvalm2 evaluates a polynomial with a matrix argument faster than the MATLAB function polyvalm. Author: James Tursa	Bruno: Done. Thanks for the suggestion. polyvalm2 now keeps all the intermediate calculations and the answer as sparse for sparse inputs.
01 Sep 2009	Sin Cos 01 Find the zero and one degree values. Author: M P	Wow, I think I am finally getting this stuff. I have to admit it took be awhile to get the meaning of your other posts, but this one for some reason just stood out. These lines from your description were the key: POSitive half unity: 51 POSitive unity: 102 After that it was simply putting this together with both of these lines: X = sin(360°) 180 = sin(360°) to get that this was a POSitive Program Of Sines (POS), or POS POS! Yeah, I finally got it! So I think you should re-title this submission as: POS POS: Sin Cos 01

Comments and Ratings on James' Files			View all 1 - 5 of 19
Updated	File	Comment by	Comments	Rating
21 Nov 2009	IEEE 754r Half Precision floating point converter Converts MATLAB or C variables to/from IEEE 754r Half Precision floating point bit pattern. Author: James Tursa	Tursa, James	Also this: #include <stdint.h>
21 Nov 2009	IEEE 754r Half Precision floating point converter Converts MATLAB or C variables to/from IEEE 754r Half Precision floating point bit pattern. Author: James Tursa	Tursa, James	I just got a report from a 64-bit linux user that the ieehalfprecision.c code did not work as posted, but he did get it to work by changing some types as follows: #define INT16_TYPE int16_t #define UINT16_TYPE uint16_t #define INT32_TYPE int32_t #define UINT32_TYPE uint32_t I do not have a 64-bit system to test with, but I would assume this works as long as your compiler supports the int16_t etc types.
12 Nov 2009	mpower2 - A faster matrix power function. mpower2 evaluates matrix to an integer power faster than the MATLAB built-in function mpower. Author: James Tursa	Tursa, James	Gianni: Raising to a power with matrix multiplies is not mathematically defined for non-square matrices. Hence mpower2 (and MATLAB's own mpower) do not support this operation. For vectors, an operation that is supported in MATLAB is the element-wise power using the .^ operator.
12 Nov 2009	mpower2 - A faster matrix power function. mpower2 evaluates matrix to an integer power faster than the MATLAB built-in function mpower. Author: James Tursa	Schena, Gianni	super... but only with square matrices as far as I understant can it work also with vectors ? regards, gianni
12 Nov 2009	polyvalm2 - A faster matrix polynomial evaluator polyvalm2 evaluates a polynomial with a matrix argument faster than the MATLAB function polyvalm. Author: James Tursa	Luong, Bruno	Neatly coded. How often do you see a Matlab stock matrix function get beaten in speed?

Top Tags Applied by James	1 - 5 of 74
external interface, mex, precision, fortran, bit

Files Tagged by James				View all 1 - 5 of 21
Updated	File	Tags	Downloads (last 30 days)	Comments	Rating
11 Nov 2009	mpower2 - A faster matrix power function. mpower2 evaluates matrix to an integer power faster than the MATLAB built-in function mpower. Author: James Tursa	matrix, power, mpower	51	2
11 Nov 2009	polyvalm2 - A faster matrix polynomial evaluator polyvalm2 evaluates a polynomial with a matrix argument faster than the MATLAB function polyvalm. Author: James Tursa	matrix, polynomial, polyvalm, mpower	36	3	5.0 5.0 \| 1 rating
23 Oct 2009	num2vpi - Converts input exactly into vpi Converts double inputs larger than 2^53-1, or char inputs with exponents, exactly into vpi. Author: James Tursa	vpi, precision, variable, integer	109	0
25 Sep 2009	Fortran mex routine mxGetClassName A drop-in replacement for the TMW Fortran API function mxGetClassName routine that does not work. Author: James Tursa	fortran, mxgetclassname, mex, class name	113	0
05 Aug 2009	num2strexact (exact version of num2str) num2strexact does exact conversion of number to string based on IEEE floating point bit pattern Author: James Tursa	num2strexact, str2num, sprintf, num2str, precision, printf	139	0

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