Changeset 2566 for branches/f4grobner/polynomial.lisp

Timestamp:

2015-06-19T17:31:46-07:00 (9 years ago)

Author:

Marek Rychlik

Message:

* empty log message *

File:

• branches/f4grobner/polynomial.lisp (modified) (2 diffs)

branches/f4grobner/polynomial.lisp

@@ -87 +87 @@
 
 (defmethod add-to ((self poly) (other poly))
+  "Adds to polynomial SELF another polynomial OTHER.
+This operation destructively modifies both polynomials.
+The result is stored in SELF. This implementation does
+no consing, entirely reusing the sells of SELF and OTHER."
   (macrolet ((lt (termlist) `(car ,termlist))
              (lc (termlist) `(r-coeff (car ,termlist))))
@@ -96 +100 @@
              (q termlist2))
             ((endp q))
-          ;; Copy all initial terms of q greater than (lt p) into p       
-          (do ()
-              ((cond 
-                 ((endp q))
-                 (t 
-                  (multiple-value-bind 
-                        (greater-p equal-p)
-                      (lex> (lt q) (lt p))
-                    (cond
-                      (greater-p 
-                       (psetf (cdr q) p
-                              q (cdr q)
-                              (cdr p) p))
-                      (equal-p
-                       (setf (lc p) (add-to (lc p) (lc q))
-                             p (cdr p))))
-                    (not greater-p))))))))))
+          (multiple-value-bind 
+                (greater-p equal-p)
+              (lex> (lt q) (lt p))
+            (cond
+              (greater-p 
+               (psetf (cdr q) p
+                      q (cdr q)
+                      (cdr p) p))
+              (equal-p
+               (setf (lc p) (add-to (lc p) (lc q))
+                     p (cdr p)
+                     q (cdr q))))
+            (not greater-p))))))
   self)