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| author | Even Rouault <even.rouault@spatialys.com> | 2018-12-19 13:00:37 +0100 |
|---|---|---|
| committer | Even Rouault <even.rouault@spatialys.com> | 2018-12-26 10:08:55 +0100 |
| commit | df574ae332d57f556fd56314883b3354cab1d0ff (patch) | |
| tree | 63a68d40d7ed7932d6329d9c7baa340bb6294f7f /src/zpoly1.cpp | |
| parent | e6de172371ea203f6393d745641d66c82b5b13e2 (diff) | |
| download | PROJ-df574ae332d57f556fd56314883b3354cab1d0ff.tar.gz PROJ-df574ae332d57f556fd56314883b3354cab1d0ff.zip | |
cpp conversion: remove useless pj_, PJ_ and proj_ filename prefixes
Diffstat (limited to 'src/zpoly1.cpp')
| -rw-r--r-- | src/zpoly1.cpp | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/src/zpoly1.cpp b/src/zpoly1.cpp new file mode 100644 index 00000000..bacb62ce --- /dev/null +++ b/src/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; +} |
