det_c |
Table of contents
Proceduredet_c ( Determinant of a double precision 3x3 matrix ) SpiceDouble det_c ( ConstSpiceDouble m1[3][3] ) AbstractCompute the determinant of a double precision 3x3 matrix. Required_ReadingNone. KeywordsMATH MATRIX Brief_I/OVARIABLE I/O DESCRIPTION -------- --- -------------------------------------------------- m1 I Matrix whose determinant is to be found. The function returns the value of the determinant found by direct application of the definition of the determinant. Detailed_Inputm1 is any double precision, 3x3 matrix. Detailed_OutputThe function returns the value of the determinant found by direct application of the definition of the determinant. ParametersNone. ExceptionsError free. FilesNone. Particularsdet_c calculates the determinant of `m1' in a single arithmetic expression which is, effectively, the expansion of `m1' about its first row. Since the calculation of the determinant involves the multiplication of numbers whose magnitudes are unrestricted, there is the possibility of floating point overflow or underflow. NO error checking or recovery is implemented in this routine. ExamplesThe numerical results shown for this example may differ across platforms. The results depend on the SPICE kernels used as input, the compiler and supporting libraries, and the machine specific arithmetic implementation. 1) Given a 3x3 double precision matrix, compute its determinant. Example code begins here. /. Program det_ex1 ./ #include <stdio.h> #include "SpiceUsr.h" int main( ) { /. Set `m1' and `m2'. ./ SpiceDouble m1 [3][3] = { {1.0, 2.0, 3.0}, {4.0, 5.0, 6.0}, {7.0, 8.0, 9.0} }; SpiceDouble m2 [3][3] = { {1.0, 2.0, 3.0}, {0.0, 5.0, 6.0}, {0.0, 0.0, 9.0} }; /. Display the determinant of `m1' and `m2'. ./ printf( "Determinant of M1: %5.2f\n", det_c ( m1 ) ); printf( "Determinant of M2: %5.2f\n", det_c ( m2 ) ); return ( 0 ); } When this program was executed on a Mac/Intel/cc/64-bit platform, the output was: Determinant of M1: 0.00 Determinant of M2: 45.00 Restrictions1) No checking is implemented to determine whether `m1' will cause overflow or underflow in the process of calculating the determinant. In most cases, this will not pose a problem. The user is required to determine if `m1' is suitable matrix for det_c to operate on. Literature_ReferencesNone. Author_and_InstitutionN.J. Bachman (JPL) J. Diaz del Rio (ODC Space) W.M. Owen (JPL) Version-CSPICE Version 1.0.1, 02-JUL-2021 (JDR) Edited the header to comply with NAIF standard. Added complete code example based on existing fragment. -CSPICE Version 1.0.0, 21-OCT-1998 (NJB) (WMO) Index_Entriesdeterminant of a d.p. 3x3_matrix |
Fri Dec 31 18:41:04 2021