+
+/* Compute the greatest common divisor of two numbers using
+ Euclid's algorithm. */
+
+static inline int
+gcd (int a, int b)
+{
+ int x, y, z;
+
+ x = abs (a);
+ y = abs (b);
+
+ while (x > 0)
+ {
+ z = y % x;
+ y = x;
+ x = z;
+ }
+
+ return y;
+}
+
+/* Compute the greatest common divisor of a VECTOR of SIZE numbers. */
+
+static inline int
+lambda_vector_gcd (lambda_vector vector, int size)
+{
+ int i;
+ int gcd1 = 0;
+
+ if (size > 0)
+ {
+ gcd1 = vector[0];
+ for (i = 1; i < size; i++)
+ gcd1 = gcd (gcd1, vector[i]);
+ }
+ return gcd1;
+}
+
+/* Returns true when the vector V is lexicographically positive, in
+ other words, when the first nonzero element is positive. */
+
+static inline bool
+lambda_vector_lexico_pos (lambda_vector v,
+ unsigned n)
+{
+ unsigned i;
+ for (i = 0; i < n; i++)
+ {
+ if (v[i] == 0)
+ continue;
+ if (v[i] < 0)
+ return false;
+ if (v[i] > 0)
+ return true;
+ }
+ return true;
+}
+