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authorEven Rouault <even.rouault@spatialys.com>2018-12-19 13:00:37 +0100
committerEven Rouault <even.rouault@spatialys.com>2018-12-26 10:08:55 +0100
commitdf574ae332d57f556fd56314883b3354cab1d0ff (patch)
tree63a68d40d7ed7932d6329d9c7baa340bb6294f7f /src/zpoly1.cpp
parente6de172371ea203f6393d745641d66c82b5b13e2 (diff)
downloadPROJ-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.cpp46
1 files changed, 46 insertions, 0 deletions
diff --git a/src/zpoly1.cpp b/src/zpoly1.cpp
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--- /dev/null
+++ b/src/zpoly1.cpp
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+/* 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;
+}