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geometric progression

Nov 19, 2022CodeCatch
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Canvas File Downloader

Nov 18, 2022AustinLeath

0 likes • 4 views

results =
{
"11345240":"Media Comment-80e47004-1719-493a-af69-a43b2652b41c",
"11345282":"zoom_3_22_21.mp4",
"11345303":"Recording-2.m4a",
"11345348":"February 12%2C 2021.mp4",
"11345826":"Lecture_Rousso_Chapter_06-2.pptx",
"11345933":"Themes_InClassAssigment.pptx",
"11346193":"Agenda – Week of March23.pptx",
"11346318":"MUJS 2370 SP2021 Updated Rhythm Changes Drills Bb - Score.pdf",
"11346319":"MUJS 2370 SP2021 Updated Rhythm Changes Drills C - Score.pdf",
"11346322":"MUJS 2370 SP2021 Updated Rhythm Changes Drills Eb - Score.pdf",
"11346323":"MUJS 2370 Updated Rhythm Changes Drills Bass - Score.pdf",
"11346381":"Anthropology with colored highlighter analysis - Mar 22 2021 - 10-36 AM.pdf",
"11346449":"Anthropology with colored highlighter analysis - Mar 22 2021 - 10-36 AM.pdf",
"11346450":"MUJS 2370 SP2021 Updated Rhythm Changes Drills Bb - Score.pdf",
"11346451":"MUJS 2370 SP2021 Updated Rhythm Changes Drills C - Score.pdf",
"11346453":"MUJS 2370 SP2021 Updated Rhythm Changes Drills Eb - Score.pdf",
"11346454":"MUJS 2370 Updated Rhythm Changes Drills Bass - Score.pdf",
"11346495":"Steinel chromatic ornamentation étude rhythm changes - Aug 23 2020 - 12-19 PM.pdf",
"11346532":"Media Comment-136242b4-7f2c-4d5d-8aa4-091f07e797cf",
"11346581":"2019 Trust Based Relationship Intervention Manual.pdf",
"11346584":"TBRI ppt.pptx",
"11346593":"Trauma informed care.ppt"
}
function NewTab(testing) {
window.open(testing, "_blank");
}
for(test in results) {
var testing = 'https://unt.instructure.com/files/' + test + '/download';
NewTab(testing);
//window.open = 'https://unt.instructure.com/files/' + test + '/download';
}

K-means clustering

Nov 19, 2022CodeCatch

0 likes • 0 views

const kMeans = (data, k = 1) => {
const centroids = data.slice(0, k);
const distances = Array.from({ length: data.length }, () =>
Array.from({ length: k }, () => 0)
);
const classes = Array.from({ length: data.length }, () => -1);
let itr = true;
while (itr) {
itr = false;
for (let d in data) {
for (let c = 0; c < k; c++) {
distances[d][c] = Math.hypot(
...Object.keys(data[0]).map(key => data[d][key] - centroids[c][key])
);
}
const m = distances[d].indexOf(Math.min(...distances[d]));
if (classes[d] !== m) itr = true;
classes[d] = m;
}
for (let c = 0; c < k; c++) {
centroids[c] = Array.from({ length: data[0].length }, () => 0);
const size = data.reduce((acc, _, d) => {
if (classes[d] === c) {
acc++;
for (let i in data[0]) centroids[c][i] += data[d][i];
}
return acc;
}, 0);
for (let i in data[0]) {
centroids[c][i] = parseFloat(Number(centroids[c][i] / size).toFixed(2));
}
}
}
return classes;
};
kMeans([[0, 0], [0, 1], [1, 3], [2, 0]], 2); // [0, 1, 1, 0]

count substrings

Nov 19, 2022CodeCatch

0 likes • 0 views

const countSubstrings = (str, searchValue) => {
let count = 0,
i = 0;
while (true) {
const r = str.indexOf(searchValue, i);
if (r !== -1) [count, i] = [count + 1, r + 1];
else return count;
}
};
countSubstrings('tiktok tok tok tik tok tik', 'tik'); // 3
countSubstrings('tutut tut tut', 'tut'); // 4

Function promisification

Nov 19, 2022CodeCatch

0 likes • 0 views

// promisify(f, true) to get array of results
function promisify(f, manyArgs = false) {
return function (...args) {
return new Promise((resolve, reject) => {
function callback(err, ...results) { // our custom callback for f
if (err) {
reject(err);
} else {
// resolve with all callback results if manyArgs is specified
resolve(manyArgs ? results : results[0]);
}
}
args.push(callback);
f.call(this, ...args);
});
};
}
// usage:
f = promisify(f, true);
f(...).then(arrayOfResults => ..., err => ...);

Check if array is empty

Nov 19, 2022CodeCatch

0 likes • 0 views

arr = [] // empty array
const isEmpty = arr => !Array.isArray(arr) || arr.length === 0;
// Examples
isEmpty([]); // true
isEmpty([1, 2, 3]); // false

graph example

Nov 19, 2022CodeCatch

0 likes • 4 views

class Graph {
constructor(directed = true) {
this.directed = directed;
this.nodes = [];
this.edges = new Map();
}
addNode(key, value = key) {
this.nodes.push({ key, value });
}
addEdge(a, b, weight) {
this.edges.set(JSON.stringify([a, b]), { a, b, weight });
if (!this.directed)
this.edges.set(JSON.stringify([b, a]), { a: b, b: a, weight });
}
removeNode(key) {
this.nodes = this.nodes.filter(n => n.key !== key);
[...this.edges.values()].forEach(({ a, b }) => {
if (a === key || b === key) this.edges.delete(JSON.stringify([a, b]));
});
}
removeEdge(a, b) {
this.edges.delete(JSON.stringify([a, b]));
if (!this.directed) this.edges.delete(JSON.stringify([b, a]));
}
findNode(key) {
return this.nodes.find(x => x.key === key);
}
hasEdge(a, b) {
return this.edges.has(JSON.stringify([a, b]));
}
setEdgeWeight(a, b, weight) {
this.edges.set(JSON.stringify([a, b]), { a, b, weight });
if (!this.directed)
this.edges.set(JSON.stringify([b, a]), { a: b, b: a, weight });
}
getEdgeWeight(a, b) {
return this.edges.get(JSON.stringify([a, b])).weight;
}
adjacent(key) {
return [...this.edges.values()].reduce((acc, { a, b }) => {
if (a === key) acc.push(b);
return acc;
}, []);
}
indegree(key) {
return [...this.edges.values()].reduce((acc, { a, b }) => {
if (b === key) acc++;
return acc;
}, 0);
}
outdegree(key) {
return [...this.edges.values()].reduce((acc, { a, b }) => {
if (a === key) acc++;
return acc;
}, 0);
}
}
const g = new Graph();
g.addNode('a');
g.addNode('b');
g.addNode('c');
g.addNode('d');
g.addEdge('a', 'c');
g.addEdge('b', 'c');
g.addEdge('c', 'b');
g.addEdge('d', 'a');
g.nodes.map(x => x.value); // ['a', 'b', 'c', 'd']
[...g.edges.values()].map(({ a, b }) => `${a} => ${b}`);
// ['a => c', 'b => c', 'c => b', 'd => a']
g.adjacent('c'); // ['b']
g.indegree('c'); // 2
g.outdegree('c'); // 1
g.hasEdge('d', 'a'); // true
g.hasEdge('a', 'd'); // false
g.removeEdge('c', 'b');
[...g.edges.values()].map(({ a, b }) => `${a} => ${b}`);
// ['a => c', 'b => c', 'd => a']
g.removeNode('c');
g.nodes.map(x => x.value); // ['a', 'b', 'd']
[...g.edges.values()].map(({ a, b }) => `${a} => ${b}`);
// ['d => a']
g.setEdgeWeight('d', 'a', 5);
g.getEdgeWeight('d', 'a'); // 5