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--- noise_simulation [2013/04/22 22:43] – created johnsoevans
+++ noise_simulation [2025/09/19 15:18] (current) – external edit 127.0.0.1
@@ Line 1: / Line 1: @@
+====== Noise Simulation - Version 5 ======
+To add noise to a simulated pattern (e.g. use the "simulate pattern from cif" command in jEdit menus you can use the function Rand_Normal(Mean, Std_Deviation); for example:
+<code topas>   xdd_out FILE load out_record out_fmt out_eqn
+   {
+       " %11.6f " = X;
+       " %11.6f\n" = Rand_Normal(Ycalc, Sqrt(Ycalc));
+   }</code>
+To test Rand_Normal then try:
+<code topas>iters 0
+yobs_eqn = 100;
+        min 0.001
+        max 100
+        del .001
+   xdd_out aac.txt load out_record out_fmt out_eqn
+   {
+       " %11.6f\n" = Abs(Rand_Normal(0, 1));
+   }</code>
+The data in AAC.TXT should obey the following:
+               Sqrt[ Sum(AAC.TXT)^2 / 100000 ] = 1