@keystonehq/alias-sampling - npm Package Compare versions

Comparing version 0.1.0 to 0.1.1

dist/index.d.ts

 type RNGFunction = () => number;
-export default function sample(probabilities: number[], outcomes?: any[], rng?: RNGFunction): {
+type AliasData = {
+    prob: number[];
+    alias: number[];
+};
+declare const next: (aliasData: AliasData, outcomes: any[], rng: RNGFunction, numOfSamples?: number) => any | any[];
+declare const sample: (probabilities: number[], outcomes?: any[], rng?: RNGFunction) => {
     next: (numOfSamples?: number) => any | any[];
 };
-export {};
+export default sample;

dist/index.js

@@ -6,17 +6,14 @@ "use strict";
         if (val < 0) {
-            throw new Error('Probabilities must be positive.');
+            throw new Error('Probability must be a positive: p[' + p.indexOf(val) + ']=' + val);
         }
         return acc + val;
     }, 0);
-    if (sum <= 0) {
+    if (sum === 0) {
         throw new Error('Probability sum must be greater than zero.');
     }
     var scaledProbabilities = p.map(function (prob) { return (prob * n) / sum; });
-    var aliasData = {
-        prob: new Array(n),
-        alias: new Array(n),
-    };
+    var aliasData = { prob: new Array(n), alias: new Array(n) };
     var small = [];
     var large = [];
-    for (var i = 0; i < n; i++) {
+    for (var i = n - 1; i >= 0; i--) {
         if (scaledProbabilities[i] < 1) {
@@ -34,3 +31,3 @@ small.push(i);
         aliasData.alias[less] = more;
-        scaledProbabilities[more] -= 1 - scaledProbabilities[less];
+        scaledProbabilities[more] = (scaledProbabilities[more] + scaledProbabilities[less]) - 1;
         if (scaledProbabilities[more] < 1) {
@@ -43,5 +40,8 @@ small.push(more);
     }
-    large.concat(small).forEach(function (g) {
-        aliasData.prob[g] = 1;
-    });
+    while (large.length > 0) {
+        aliasData.prob[large.pop()] = 1;
+    }
+    while (small.length > 0) {
+        aliasData.prob[small.pop()] = 1;
+    }
     return aliasData;
@@ -64,3 +64,3 @@ };
 };
-function sample(probabilities, outcomes, rng) {
+var sample = function (probabilities, outcomes, rng) {
     if (rng === void 0) { rng = Math.random; }
@@ -70,2 +70,5 @@ if (!Array.isArray(probabilities)) {
     }
+    if (probabilities.length === 0) {
+        throw new Error('Probabilities array must not be empty.');
+    }
     var n = probabilities.length;
@@ -80,3 +83,3 @@ var indexedOutcomes = outcomes !== null && outcomes !== void 0 ? outcomes : Array.from({ length: n }, function (_, i) { return i; });
     };
-}
+};
 exports.default = sample;

package.json

 {
   "name": "@keystonehq/alias-sampling",
-  "version": "0.1.0",
+  "version": "0.1.1",
   "description": "A Node.js module for efficient sampling from a discrete probability distribution using the alias method.",
@@ -5,0 +5,0 @@ "main": "dist/index.js",

Fixed alerts

New author

Supply chain risk

A new npm collaborator published a version of the package for the first time. New collaborators are usually benign additions to a project, but do indicate a change to the security surface area of a package.

Found 1 instance in 1 package

Improved metrics

Total package byte prevSize

7155

increased by6.27%

Lines of code

89

increased by9.88%

Number of medium supply chain risk alerts

0

decreased by-100%

No dependency changes