feat:node-modules

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

@@ -0,0 +1,52 @@
+// 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
+import { csTdfs } from './csTdfs.js';
+
+/**
+ * Post order a tree of forest
+ *
+ * @param {Array}   parent          The tree or forest
+ * @param {Number}  n               Number of columns
+ */
+export function csPost(parent, n) {
+  // check inputs
+  if (!parent) {
+    return null;
+  }
+  // vars
+  var k = 0;
+  var j;
+  // allocate result
+  var post = []; // (n)
+  // workspace, head: first n entries, next: next n entries, stack: last n entries
+  var w = []; // (3 * n)
+  var head = 0;
+  var next = n;
+  var stack = 2 * n;
+  // initialize workspace
+  for (j = 0; j < n; j++) {
+    // empty linked lists
+    w[head + j] = -1;
+  }
+  // traverse nodes in reverse order
+  for (j = n - 1; j >= 0; j--) {
+    // check j is a root
+    if (parent[j] === -1) {
+      continue;
+    }
+    // add j to list of its parent
+    w[next + j] = w[head + parent[j]];
+    w[head + parent[j]] = j;
+  }
+  // loop nodes
+  for (j = 0; j < n; j++) {
+    // skip j if it is not a root
+    if (parent[j] !== -1) {
+      continue;
+    }
+    // depth-first search
+    k = csTdfs(j, k, w, head, next, post, stack);
+  }
+  return post;
+}