Initial data commit

Task/Euler-method/PL-I/euler-method.pli

@@ -0,0 +1,44 @@
+test: procedure options (main); /* 3 December 2012 */
+
+   declare (x, y, z) float;
+   declare (T0 initial (100), Tr initial (20)) float;
+   declare k float initial (0.07);
+   declare t fixed binary;
+   declare h fixed binary;
+
+   x, y, z = T0;
+   /* Step size is 2 seconds */
+   h = 2;
+   put skip data (h);
+   put skip list ('  t    By formula', 'By Euler');
+   do t = 0 to 100 by 2;
+      put skip edit (t, Tr + (T0 - Tr)/exp(k*t), x) (f(3), 2 f(17,10));
+      x = x + h*f(t, x);
+   end;
+
+   /* Step size is 5 seconds */
+   h = 5;
+   put skip data (h);
+   put skip list ('  t    By formula', 'By Euler');
+   do t = 0 to 100 by 5;
+      put skip edit ( t, Tr + (T0 - Tr)/exp(k*t), y) (f(3), 2 f(17,10));
+      y = y + h*f(t, y);
+   end;
+
+   /* Step size is 10 seconds */
+   h = 10;
+   put skip data (h);
+   put skip list ('  t    By formula', 'By Euler');
+   do t = 0 to 100 by 10;
+      put skip edit (t, Tr + (T0 - Tr)/exp(k*t), z) (f(3), 2 f(17,10));
+      z = z + h*f(t, z);
+   end;
+
+f: procedure (dummy, T) returns (float);
+   declare dummy  fixed binary;
+   declare T float;
+
+   return ( -k*(T - Tr) );
+end f;
+
+end test;