feat:node-modules

node_modules/mathjs/lib/esm/function/algebra/sparse/csLeaf.js

@@ -0,0 +1,56 @@
+// Copyright (c) 2006-2024, Timothy A. Davis, All Rights Reserved.
+// SPDX-License-Identifier: LGPL-2.1+
+// https://github.com/DrTimothyAldenDavis/SuiteSparse/tree/dev/CSparse/Source
+
+/**
+ * This function determines if j is a leaf of the ith row subtree.
+ * Consider A(i,j), node j in ith row subtree and return lca(jprev,j)
+ *
+ * @param {Number}  i               The ith row subtree
+ * @param {Number}  j               The node to test
+ * @param {Array}   w               The workspace array
+ * @param {Number}  first           The index offset within the workspace for the first array
+ * @param {Number}  maxfirst        The index offset within the workspace for the maxfirst array
+ * @param {Number}  prevleaf        The index offset within the workspace for the prevleaf array
+ * @param {Number}  ancestor        The index offset within the workspace for the ancestor array
+ *
+ * @return {Object}
+ */
+export function csLeaf(i, j, w, first, maxfirst, prevleaf, ancestor) {
+  var s, sparent;
+
+  // our result
+  var jleaf = 0;
+  var q;
+
+  // check j is a leaf
+  if (i <= j || w[first + j] <= w[maxfirst + i]) {
+    return -1;
+  }
+  // update max first[j] seen so far
+  w[maxfirst + i] = w[first + j];
+  // jprev = previous leaf of ith subtree
+  var jprev = w[prevleaf + i];
+  w[prevleaf + i] = j;
+
+  // check j is first or subsequent leaf
+  if (jprev === -1) {
+    // 1st leaf, q = root of ith subtree
+    jleaf = 1;
+    q = i;
+  } else {
+    // update jleaf
+    jleaf = 2;
+    // q = least common ancester (jprev,j)
+    for (q = jprev; q !== w[ancestor + q]; q = w[ancestor + q]);
+    for (s = jprev; s !== q; s = sparent) {
+      // path compression
+      sparent = w[ancestor + s];
+      w[ancestor + s] = q;
+    }
+  }
+  return {
+    jleaf,
+    q
+  };
+}