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| author | Even Rouault <even.rouault@spatialys.com> | 2018-12-18 20:24:11 +0100 |
|---|---|---|
| committer | Even Rouault <even.rouault@spatialys.com> | 2018-12-26 10:08:53 +0100 |
| commit | 610957f7035242f15743c399ffd429b92bc36206 (patch) | |
| tree | 73f0d51147e2f4860c4bfc875f7a4bf9359386d4 /src/pj_zpoly1.cpp | |
| parent | 355d681ed88019e97742344bd642c2fd97e700a1 (diff) | |
| download | PROJ-610957f7035242f15743c399ffd429b92bc36206.tar.gz PROJ-610957f7035242f15743c399ffd429b92bc36206.zip | |
cpp conversion: minimal steps to fix compilation errors, not warnings
Diffstat (limited to 'src/pj_zpoly1.cpp')
| -rw-r--r-- | src/pj_zpoly1.cpp | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/src/pj_zpoly1.cpp b/src/pj_zpoly1.cpp new file mode 100644 index 00000000..bacb62ce --- /dev/null +++ b/src/pj_zpoly1.cpp @@ -0,0 +1,46 @@ +/* evaluate complex polynomial */ +#include "projects.h" +/* note: coefficients are always from C_1 to C_n +** i.e. C_0 == (0., 0) +** n should always be >= 1 though no checks are made +*/ + COMPLEX +pj_zpoly1(COMPLEX z, const COMPLEX *C, int n) { + COMPLEX a; + double t; + + a = *(C += n); + while (n-- > 0) { + a.r = (--C)->r + z.r * (t = a.r) - z.i * a.i; + a.i = C->i + z.r * a.i + z.i * t; + } + a.r = z.r * (t = a.r) - z.i * a.i; + a.i = z.r * a.i + z.i * t; + return a; +} +/* evaluate complex polynomial and derivative */ + COMPLEX +pj_zpolyd1(COMPLEX z, const COMPLEX *C, int n, COMPLEX *der) { + COMPLEX a, b; + double t; + int first = 1; + + a = *(C += n); + b = a; + while (n-- > 0) { + if (first) { + first = 0; + } else { + b.r = a.r + z.r * (t = b.r) - z.i * b.i; + b.i = a.i + z.r * b.i + z.i * t; + } + a.r = (--C)->r + z.r * (t = a.r) - z.i * a.i; + a.i = C->i + z.r * a.i + z.i * t; + } + b.r = a.r + z.r * (t = b.r) - z.i * b.i; + b.i = a.i + z.r * b.i + z.i * t; + a.r = z.r * (t = a.r) - z.i * a.i; + a.i = z.r * a.i + z.i * t; + *der = b; + return a; +} |
