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author | Eric S. Raymond <esr@thyrsus.com> | 2014-09-20 11:55:11 -0400 |
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committer | Eric S. Raymond <esr@thyrsus.com> | 2014-09-20 11:55:11 -0400 |
commit | a90472a1caf5b871792c5a568ee3d0b389a47643 (patch) | |
tree | 397f6b32d582c74a1cfc24365f950d9d79bae85d /test_matrix.c | |
parent | 31ea5b65445baf0dce18311be805dafec4f725c3 (diff) | |
download | gpsd-a90472a1caf5b871792c5a568ee3d0b389a47643.tar.gz |
Integrate a matrix-algebra regression test.
Diffstat (limited to 'test_matrix.c')
-rw-r--r-- | test_matrix.c | 70 |
1 files changed, 52 insertions, 18 deletions
diff --git a/test_matrix.c b/test_matrix.c index bbbaffeb..0f8f17d1 100644 --- a/test_matrix.c +++ b/test_matrix.c @@ -8,6 +8,7 @@ #include <stdbool.h> #include <stdlib.h> #include <stdio.h> +#include <math.h> #include "matrix.h" @@ -18,29 +19,62 @@ # define UNUSED #endif -static double a[4][4] = { - {1, 2, 3, 4}, - {5, 6, 7, 8}, - {9, 10, 11, 12}, - {13, 14, 15, 16}}; -static double ainv[4][4] = { - {-0.0028097262031538, 0.0073561782338441, 0.0040563991615249, -0.0086028511922152}, - {-0.0018928965221056, 0.00016424848911584, 0.0070451831437969, -0.0053165351108071}, - {0.031623219351165, 0.00010097243183351, -0.020259108723076, -0.011465083059922}, - {0.031734962175727, -0.10943930681752, -0.52209748013199,1.5998018247738}, +static struct { + double mat[4][4]; + double inv[4][4]; +} inverses[] = { + /* identity matrix is self-inverse */ + { + .mat = {{1,0,0,0}, {0,1,0,0}, {0,0,1,0}, {0,0,0,1}}, + .inv = {{1,0,0,0}, {0,1,0,0}, {0,0,1,0}, {0,0,0,1}}, + }, + /* inverse of a diagonal matrix has reciprocal values */ + { + .mat = {{10,0,0,0}, {0,10,0,0}, {0,0,10,0}, {0,0,0,10}}, + .inv = {{0.1,0,0,0}, {0,0.1,0,0}, {0,0,0.1,0}, {0,0,0,0.1}}, + }, }; -int main(int argc UNUSED, char *argv[] UNUSED) +static void dump(const char *label, double m[4][4]) { - double inv[4][4]; + printf("%s:\n", label); + printf("%f, %f, %f, %f\n", m[0][0], m[0][1], m[0][2], m[0][3]); + printf("%f, %f, %f, %f\n", m[1][0], m[1][1], m[1][2], m[1][3]); + printf("%f, %f, %f, %f\n", m[2][0], m[2][1], m[2][2], m[2][3]); + printf("%f, %f, %f, %f\n", m[3][0], m[3][1], m[3][2], m[3][3]); +} + +static bool check_diag(int n, double a[4][4], double b[4][4]) +{ +#define approx(x, y) (fabs(x - y) < 0.0001) - matrix_invert(a, inv); - printf("%f %f %f %f\n", - inv[0][0] - ainv[0][0], - inv[1][1] - ainv[1][1], - inv[2][2] - ainv[2][2], - inv[3][3] - ainv[3][3] + if (approx(b[0][0], a[0][0]) && approx(b[1][1], a[1][1]) && + approx(b[2][2], a[2][2]) && approx(b[3][3], a[3][3])) + return true; + + dump("a", a); + dump("b", b); + printf("Test %d residuals: %f %f %f %f\n", + n, + b[0][0] - a[0][0], + b[1][1] - a[1][1], + b[2][2] - a[2][2], + b[3][3] - a[3][3] ); + return true; +} + +int main(int argc UNUSED, char *argv[] UNUSED) +{ + size_t i; + + for (i = 0; i < sizeof(inverses) / sizeof(inverses[0]); i++) { + double inverse[4][4]; + matrix_invert(inverses[i].mat, inverse); + if (!check_diag(i, inverse, inverses[i].inv)) + break; + } + printf("Matrix-algebra regression test succeeded\n"); exit(0); } |