- added backwards calculation of hkl from four circle angles. This

required inclusion of a matrix package.
- modified  counter error handling to send a Stop when the _BAD_BUSY
  error is received.
- added an environment interface to the general controller stuff in choco.*
  Also added setting a parameter directly at the controller object.
- Added a driver for the ETH High Temperature Furnace to be used at
  SANS.

matrix/matsub.c

@@ -0,0 +1,42 @@
+/*
+*-----------------------------------------------------------------------------
+*	file:	matsub.c
+*	desc:	matrix substraction
+*	by:	ko shu pui, patrick
+*	date:	24 nov 91 v0.1
+*	revi:
+*	ref:
+*       [1] Mary L.Boas, "Mathematical Methods in the Physical Sciene,"
+*	John Wiley & Sons, 2nd Ed., 1983. Chap 3.
+*
+*-----------------------------------------------------------------------------
+*/
+#include <stdio.h>
+#include "matrix.h"
+
+/*
+*-----------------------------------------------------------------------------
+*	funct:	mat_sub
+*	desct:	subtraction of two matrice
+*	given:	A, B = compatible matrice to be added
+*	retrn:	NULL if malloc() fails
+*		else allocated matrix of A - B
+*	comen:
+*-----------------------------------------------------------------------------
+*/
+MATRIX mat_sub( A, B )
+MATRIX A, B;
+{
+	int	i, j;
+	MATRIX	C;
+
+	if ((C = mat_creat( MatRow(A), MatCol(A), UNDEFINED )) == NULL)
+		return (NULL);
+
+	for (i=0; i<MatRow(A); i++)
+	for (j=0; j<MatCol(A); j++)
+		{
+		C[i][j] = A[i][j] - B[i][j];
+		}
+	return (C);
+}