diff -r d59bea55db9b -r c445c931472f examples/cf12a.mod
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/examples/cf12a.mod	Mon Dec 06 13:09:21 2010 +0100
@@ -0,0 +1,81 @@
+/*
+
+  Curve fitting problem 12.11(a) H P Williams "Model Building in Mathematical Programming"
+
+  Dr. H J Mackenzie
+  HARD software
+  hjm@hardsoftware.com
+
+  2006-01-05
+
+ */
+
+# set of points
+
+set I;
+
+# independent variable
+
+param x {i in I};
+
+# dependent variable
+
+param y {i in I};
+
+# output input values
+
+printf {i in I} "x = %.1f; y = %.1f\n", x[i], y[i];
+
+# define equation variables
+
+var a;
+
+var b;
+
+var u {i in I}, >= 0;
+
+var v {i in I}, >= 0;
+
+# define objective function
+
+minimize error: sum {i in I} u[i] + sum {i in I} v[i];
+
+# define equation constraint
+
+s.t. equation {i in I} : b * x[i] + a + u[i] - v[i] = y[i];
+
+solve;
+
+printf "y = %.4fx + %.4f\n", b, a;
+
+/*
+ *
+ * DATA section
+ *
+ */
+
+data;
+
+param : I :   x    y :=
+        1     0    1
+        2   0.5  0.9
+        3     1  0.7
+        4   1.5  1.5
+        5   1.9    2
+        6   2.5  2.4
+        7     3  3.2
+        8   3.5    2
+        9     4  2.7
+       10   4.5  3.5
+       11     5    1
+       12   5.5    4
+       13     6  3.6
+       14   6.6  2.7
+       15     7  5.7
+       16   7.6  4.6
+       17   8.5    6
+       18     9  6.8
+       19    10  7.3
+;
+
+end;