replace robinson coefficients table, add test (#113)

git-svn-id: http://svn.osgeo.org/metacrs/proj/trunk@2374 4e78687f-474d-0410-85f9-8d5e500ac6b2

1 files changed, 55 insertions, 42 deletions

diff --git a/src/PJ_robin.c b/src/PJ_robin.c
index 71dac1e3..39513e2a 100644
--- a/src/PJ_robin.c
+++ b/src/PJ_robin.c
@@ -3,49 +3,62 @@
 PROJ_HEAD(robin, "Robinson") "\n\tPCyl., Sph.";
 #define V(C,z) (C.c0 + z * (C.c1 + z * (C.c2 + z * C.c3)))
 #define DV(C,z) (C.c1 + z * (C.c2 + C.c2 + z * 3. * C.c3))
-/* note: following terms based upon 5 deg. intervals in degrees. */
-static struct COEFS {
+
+/* 
+note: following terms based upon 5 deg. intervals in degrees.
+
+Some background on these coefficients is available at:
+
+http://article.gmane.org/gmane.comp.gis.proj-4.devel/6039
+http://trac.osgeo.org/proj/ticket/113
+*/
+
+struct COEFS {
 	float c0, c1, c2, c3;
-} X[] = {
-    {1,	-5.67239e-12,	-7.15511e-05,	3.11028e-06},
-    {0.9986,	-0.000482241,	-2.4897e-05,	-1.33094e-06},
-    {0.9954,	-0.000831031,	-4.4861e-05,	-9.86588e-07},
-    {0.99,	-0.00135363,	-5.96598e-05,	3.67749e-06},
-    {0.9822,	-0.00167442,	-4.4975e-06,	-5.72394e-06},
-    {0.973,	-0.00214869,	-9.03565e-05,	1.88767e-08},
-    {0.96,	-0.00305084,	-9.00732e-05,	1.64869e-06},
-    {0.9427,	-0.00382792,	-6.53428e-05,	-2.61493e-06},
-    {0.9216,	-0.00467747,	-0.000104566,	4.8122e-06},
-    {0.8962,	-0.00536222,	-3.23834e-05,	-5.43445e-06},
-    {0.8679,	-0.00609364,	-0.0001139,	3.32521e-06},
-    {0.835,	-0.00698325,	-6.40219e-05,	9.34582e-07},
-    {0.7986,	-0.00755337,	-5.00038e-05,	9.35532e-07},
-    {0.7597,	-0.00798325,	-3.59716e-05,	-2.27604e-06},
-    {0.7186,	-0.00851366,	-7.0112e-05,	-8.63072e-06},
-    {0.6732,	-0.00986209,	-0.000199572,	1.91978e-05},
-    {0.6213,	-0.010418,	8.83948e-05,	6.24031e-06},
-    {0.5722,	-0.00906601,	0.000181999,	6.24033e-06},
-    {0.5322, 0.,0.,0.}  },
-Y[] = {
-    {0,	0.0124,	3.72529e-10,	1.15484e-09},
-    {0.062,	0.0124001,	1.76951e-08,	-5.92321e-09},
-    {0.124,	0.0123998,	-7.09668e-08,	2.25753e-08},
-    {0.186,	0.0124008,	2.66917e-07,	-8.44523e-08},
-    {0.248,	0.0123971,	-9.99682e-07,	3.15569e-07},
-    {0.31,	0.0124108,	3.73349e-06,	-1.1779e-06},
-    {0.372,	0.0123598,	-1.3935e-05,	4.39588e-06},
-    {0.434,	0.0125501,	5.20034e-05,	-1.00051e-05},
-    {0.4958,	0.0123198,	-9.80735e-05,	9.22397e-06},
-    {0.5571,	0.0120308,	4.02857e-05,	-5.2901e-06},
-    {0.6176,	0.0120369,	-3.90662e-05,	7.36117e-07},
-    {0.6769,	0.0117015,	-2.80246e-05,	-8.54283e-07},
-    {0.7346,	0.0113572,	-4.08389e-05,	-5.18524e-07},
-    {0.7903,	0.0109099,	-4.86169e-05,	-1.0718e-06},
-    {0.8435,	0.0103433,	-6.46934e-05,	5.36384e-09},
-    {0.8936,	0.00969679,	-6.46129e-05,	-8.54894e-06},
-    {0.9394,	0.00840949,	-0.000192847,	-4.21023e-06},
-    {0.9761,	0.00616525,	-0.000256001,	-4.21021e-06},
-    {1., 0.,0.,0} };
+};
+
+static const struct COEFS X[] = {
+    {1, 2.2199e-17, -7.15515e-05, 3.1103e-06},
+    {0.9986, -0.000482243, -2.4897e-05, -1.3309e-06},
+    {0.9954, -0.00083103, -4.48605e-05, -9.86701e-07},
+    {0.99, -0.00135364, -5.9661e-05, 3.6777e-06},
+    {0.9822, -0.00167442, -4.49547e-06, -5.72411e-06},
+    {0.973, -0.00214868, -9.03571e-05, 1.8736e-08},
+    {0.96, -0.00305085, -9.00761e-05, 1.64917e-06},
+    {0.9427, -0.00382792, -6.53386e-05, -2.6154e-06},
+    {0.9216, -0.00467746, -0.00010457, 4.81243e-06},
+    {0.8962, -0.00536223, -3.23831e-05, -5.43432e-06},
+    {0.8679, -0.00609363, -0.000113898, 3.32484e-06},
+    {0.835, -0.00698325, -6.40253e-05, 9.34959e-07},
+    {0.7986, -0.00755338, -5.00009e-05, 9.35324e-07},
+    {0.7597, -0.00798324, -3.5971e-05, -2.27626e-06},
+    {0.7186, -0.00851367, -7.01149e-05, -8.6303e-06},
+    {0.6732, -0.00986209, -0.000199569, 1.91974e-05},
+    {0.6213, -0.010418, 8.83923e-05, 6.24051e-06},
+    {0.5722, -0.00906601, 0.000182, 6.24051e-06},
+    {0.5322, -0.00677797, 0.000275608, 6.24051e-06}
+};
+static const struct COEFS Y[] = {
+    {-5.20417e-18, 0.0124, 1.21431e-18, -8.45284e-11},
+    {0.062, 0.0124, -1.26793e-09, 4.22642e-10},
+    {0.124, 0.0124, 5.07171e-09, -1.60604e-09},
+    {0.186, 0.0123999, -1.90189e-08, 6.00152e-09},
+    {0.248, 0.0124002, 7.10039e-08, -2.24e-08},
+    {0.31, 0.0123992, -2.64997e-07, 8.35986e-08},
+    {0.372, 0.0124029, 9.88983e-07, -3.11994e-07},
+    {0.434, 0.0123893, -3.69093e-06, -4.35621e-07},
+    {0.4958, 0.0123198, -1.02252e-05, -3.45523e-07},
+    {0.5571, 0.0121916, -1.54081e-05, -5.82288e-07},
+    {0.6176, 0.0119938, -2.41424e-05, -5.25327e-07},
+    {0.6769, 0.011713, -3.20223e-05, -5.16405e-07},
+    {0.7346, 0.0113541, -3.97684e-05, -6.09052e-07},
+    {0.7903, 0.0109107, -4.89042e-05, -1.04739e-06},
+    {0.8435, 0.0103431, -6.4615e-05, -1.40374e-09},
+    {0.8936, 0.00969686, -6.4636e-05, -8.547e-06},
+    {0.9394, 0.00840947, -0.000192841, -4.2106e-06},
+    {0.9761, 0.00616527, -0.000256, -4.2106e-06},
+    {1, 0.00328947, -0.000319159, -4.2106e-06}
+};
 #define FXC	0.8487
 #define FYC	1.3523
 #define C1	11.45915590261646417544