Changeset 5a640f in git

Timestamp:

Aug 22, 2017, 2:45:37 PM (7 years ago)

Author:

Karim Abou Zeid <karim23697@…>

Branches:

(u'spielwiese', 'fe61d9c35bf7c61f2b6cbf1b56e25e2f08d536cc')

Children:

a62db6acb39329a175a16c23ac737917e158e04d

Parents:

8c0eaaaf75a8408a9638e8ca5445961fe9974e7c

Message:

Optimized standardword computation performance

File:

• Singular/LIB/fpadim.lib (modified) (3 diffs)

Singular/LIB/fpadim.lib

@@ -1422 +1422 @@
     }
   }
-  ideal V = lpStandardWords(G, l - 1); // vertices
-  int n = size(V);
+  list LG = lpId2ivLi(G);
+  list SW = ivStandardWords(LG, l - 1); // vertices
+  int n = size(SW);
   intmat UG[n][n]; // Ufnarovskij graph
   for (int i = 1; i <= n; i++) {
     for (int j = 1; j <= n; j++) {
-      // V[i] = v, V[j] = w [Studzinski page 76]
-      intvec v = lp2iv(V[i]);
-      intvec w = lp2iv(V[j]);
+      // [Studzinski page 76]
+      intvec v = SW[i];
+      intvec w = SW[j];
       intvec v_overlap;
       intvec w_overlap;
@@ -1439 +1440 @@
       intvec vw = v;
       vw[l] = w[l-1];
-      if (v_overlap == w_overlap && !divides(G, vw)) {
+      if (v_overlap == w_overlap && !ivdivides(LG, vw)) {
         UG[i,j] = 1;
       }
@@ -1447 +1448 @@
 }
 
-proc lpStandardWords(ideal G, int length) {
+proc ivStandardWords(list G, int length) {
   if (length == 0) {
-    return (1);
+    return (0); // iv = 0 means monom = 1
   }
   int lV = attrib(basering, "lV"); // variable count
-  // recursion could cause problems
-  ideal prevWords = lpStandardWords(G, length - 1);
-  ideal words;
+  list prevWords = ivStandardWords(G, length - 1);
+  list words;
   for (int i = 1; i <= lV; i++) {
     for (int j = 1; j <= size(prevWords); j++) {
-      int placeShift = (length - 1) * lV; // letterplace
-      // multiply every previous word with every variable
-      poly word = prevWords[j] * var(i + placeShift);
+      intvec word = prevWords[j];
+      word[length] = i;
       // assumes that G is simplified!
-      if (!divides(G, lp2iv(word))) {
-        words = words, word;
-      }
-    }
-  }
-  words = simplify(words, 2); // remove zeroes
+      if (!ivdivides(G, word)) {
+        words = insert(words, word);
+      }
+    }
+  }
   return (words);
 }
 
-proc divides(ideal G, intvec iv) {
+static proc ivdivides(list G, intvec iv) {
   for (int k = 1; k <= size(G); k++) {
-    if (isIF(lp2iv(G[k]), iv)) {
+    if (isIF(G[k], iv)) {
       return (1);
     } else {