1 files changed, 97 insertions, 0 deletions
diff --git a/bayrate/player.cpp b/bayrate/player.cpp
new file mode 100644
index 0000000..ad4095b
--- /dev/null
+++ b/bayrate/player.cpp
@@ -0,0 +1,97 @@
+/*************************************************************************************
+
+	Copyright 2010 Philip Waldron
+	
+    This file is part of BayRate.
+
+    BayRate is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    BayRate is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with BayRate.  If not, see <http://www.gnu.org/licenses/>.
+    
+***************************************************************************************/
+
+#include <gsl/gsl_spline.h>
+#include "player.h"
+
+player::player(void)
+{
+}
+
+player::~player(void)
+{
+}
+
+/****************************************************************
+
+calc_init_sigma (double seed) 
+
+Provides a sigma value for a new player entering the rating
+system for the first time.  Value depends on the seed rating of
+the player, with the sigma increasing as the nominal rating
+decreases.
+
+Data is interpolated for points away from the ratings corresponding
+to the midpoints of each rank. 
+
+*****************************************************************/
+double player::calc_init_sigma (double seed) {
+	/* Data is extracted from Accelrat output, with ratings (r[])
+	   offset by 1.0 towards 0 (i.e., -5.5 -> -4.5, +4.5->+3.5) in
+	   order to compensate for the jump across the dan boundary  */
+	double r[] = {-49.5, -48.5, -47.5, -46.5, -45.5,
+						-44.5, -43.5, -42.5, -41.5, -40.5,
+						-39.5, -38.5, -37.5, -36.5, -35.5,
+						-34.5, -33.5, -32.5, -31.5, -30.5,
+						-29.5, -28.5, -27.5, -26.5, -25.5,
+						-24.5, -23.5, -22.5, -21.5, -20.5,
+						-19.5, -18.5, -17.5, -16.5, -15.5,
+						-14.5, -13.5, -12.5, -11.5, -10.5,
+						-9.5, -8.5, -7.5, -6.5, -5.5,
+						-4.5, -3.5, -2.5, -1.5, -0.5,
+						0.5, 1.5, 2.5, 3.5, 4.5,
+						5.5, 6.5, 7.5, 8.5};
+					
+	double s[] = {5.73781, 5.63937, 5.54098, 5.44266, 5.34439,
+						5.24619, 5.14806, 5.05000, 4.95202, 4.85412,
+						4.75631, 4.65859, 4.56098, 4.46346, 4.36606,
+						4.26878, 4.17163, 4.07462, 3.97775, 3.88104,
+						3.78451, 3.68816, 3.59201, 3.49607, 3.40037,
+						3.30492, 3.20975, 3.11488, 3.02035, 2.92617,
+						2.83240, 2.73907, 2.64622, 2.55392, 2.46221,
+						2.37118, 2.28090, 2.19146, 2.10297, 2.01556,
+						1.92938, 1.84459, 1.76139, 1.68003, 1.60078,
+						1.52398, 1.45000, 1.37931, 1.31244, 1.25000,
+						1.19269, 1.14127, 1.09659, 1.05948, 1.03078,
+						1.01119, 1.00125, 1.00000, 1.00000};
+	double result;
+						
+	if (seed > 7.5)
+		return 1.0;
+	else if (seed < -50.5)
+		// If you're seeding someone below 50 kyu, you're up to no good. :)
+		return 6.0;
+		
+	gsl_interp_accel *acc    = gsl_interp_accel_alloc ();
+	gsl_spline       *spline = gsl_spline_alloc (gsl_interp_cspline, 59);
+     
+   gsl_spline_init (spline, r, s, 59);
+   
+   if (seed > 0)  
+   	result = gsl_spline_eval (spline, seed-1.0, acc);
+   else
+   	result = gsl_spline_eval (spline, seed+1.0, acc);
+   
+   gsl_spline_free (spline);
+   gsl_interp_accel_free (acc);
+
+	return result;
+}
+\ No newline at end of file