exposed subresultants aka psc-chain procedure

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>

src/api/z3_polynomial.h

@@ -0,0 +1,45 @@
+/*++
+Copyright (c) 2012 Microsoft Corporation
+
+Module Name:
+
+    z3_polynomial.h
+
+Abstract:
+
+    Additional APIs for polynomials.
+
+Author:
+
+    Leonardo de Moura (leonardo) 2012-12-09
+
+Notes:
+    
+--*/
+
+#ifndef _Z3_POLYNOMIAL_H_
+#define _Z3_POLYNOMIAL_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif // __cplusplus
+
+    /**
+       \brief Return the nonzero subresultants of \c p and \c q with respect to the "variable" \c x.
+       
+       \pre \c p, \c q and \c x are Z3 expressions where \c p and \c q are arithmetic terms.
+       Note that, any subterm that cannot be viewed as a polynomial is assumed to be a variable.
+       Example: f(a) is a considered to be a variable in the polynomial   
+                  
+       f(a)*f(a) + 2*f(a) + 1 
+
+       def_API('Z3_polynomial_subresultants', AST_VECTOR, (_in(CONTEXT), _in(AST), _in(AST), _in(AST)))
+    */
+    Z3_ast_vector Z3_API Z3_polynomial_subresultants(__in Z3_context c, __in Z3_ast p, __in Z3_ast q, __in Z3_ast x);
+
+
+#ifdef __cplusplus
+};
+#endif // __cplusplus
+
+#endif