Changeset 1128

Timestamp:

2015-06-10T18:08:43-07:00 (9 years ago)

Author:

Marek Rychlik

Message:

* empty log message *

File:

• branches/f4grobner/polynomial.lisp (modified) (3 diffs)

branches/f4grobner/polynomial.lisp

@@ -243 +243 @@
                            0))
 
+(defun poly-eval-scalar (expr 
+                         &optional
+                           (ring *ring-of-integers*)
+                         &aux 
+                           (order #'lex>))
+  "Evaluate a scalar expression EXPR in ring RING."
+  (poly-lc (poly-eval expr nil ring order)))
+
 (defun poly-eval (expr vars 
                   &optional 
@@ -251 +259 @@
                     (ring-and-order (make-ring-and-order :ring ring :order order)))
   (labels ((p-eval (arg) (poly-eval arg vars ring order))
-           (p-eval-scalar (arg) (poly-lc (poly-eval arg nil ring order)))
            (p-eval-list (args) (mapcar #'p-eval args))
            (p-add (x y) (poly-add ring-and-order x y)))
     (cond
+      ((null expr) (error "Empty expression"))
       ((eql expr 0) (make-poly-zero))
       ((member expr vars :test #'equalp)
@@ -282 +290 @@
              ;; A special case (/ ?), the inverse
              (coerce-coeff ring (apply (ring-div ring) (cdr expr)) vars))
-            ((endp (cdddr expr))
+            (t
              (let ((num (p-eval (cadr expr)))
-                   (denom-inverse (p-eval-scalar `(/ (ring-unit ring) @,(cddr expr)))))
-               (scalar-times-poly ring denom-inverse num)))
-            (t 
-             ;; TODO: Make this work
-             (let ((num (p-eval (cadr expr)))
-                   (denom-inverse (print (funcall (ring-div ring) (cons (ring-unit ring) (cddr expr))))))
+                   (denom-inverse (poly-eval-scalar '(/ 1 2 3) ring))
+                   ;;(denom-inverse (p-eval-scalar `(/ (ring-unit ring) @,(cddr expr))))
+                   )
                (scalar-times-poly ring denom-inverse num)))))
          (expt