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Redux Setup

CHS
0 likes • Mar 11, 2021 • 0 views
JavaScript
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Tree Traversal

CHS
0 likes • Oct 16, 2023 • 7 views
JavaScript
class TreeNode {
constructor(data, depth) {
this.data = data;
this.children = [];
this.depth = depth;
}
}
function buildNaryTree(hosts) {
const nodeMap = {};
// Step 1: Create a map of nodes using fqdn as the key
hosts.forEach((host) => {
nodeMap[host.fqdn] = new TreeNode(host, 0); // Initialize depth to 0
});
// Step 2: Iterate through the array and add each node to its parent's list of children
hosts.forEach((host) => {
if (host.displayParent) {
if (nodeMap[host.displayParent]) {
const parent = nodeMap[host.displayParent];
const node = nodeMap[host.fqdn];
node.depth = parent.depth + 1; // Update the depth
parent.children.push(node);
} else {
console.error(`Parent with fqdn ${host.displayParent} not found for ${host.fqdn}`);
}
}
});
// Find the root nodes (nodes with no parent)
const rootNodes = hosts.filter((host) => !host.displayParent).map((host) => nodeMap[host.fqdn]);
return rootNodes;
}
function treeToObjects(node) {
const result = [];
function inOrder(node) {
if (!node) {
return;
}
// Visit the current node and add it to the result
result.push(node.data);
// Visit children nodes first
node.children.forEach((child) => {
inOrder(child);
});
}
inOrder(node);
return result;
}
// Usage example
const hosts = [
{
fqdn: 'fqdn_1',
display_name: 'Host 1',
},
{
fqdn: 'fqdn_2',
display_name: 'Host 2',
displayParent: 'fqdn_1',
},
{
fqdn: 'fqdn_3',
display_name: 'Host 3'
},
{
fqdn: 'fqdn_4',
display_name: 'Host 4',
displayParent: 'fqdn_3',
},
{
fqdn: 'fqdn_5',
display_name: 'Host 5',
displayParent: 'fqdn_1',
},
];
const tree = buildNaryTree(hosts);
// Function to convert the tree to an array of objects
function convertTreeToArray(nodes) {
const result = [];
nodes.forEach((node) => {
result.push(...treeToObjects(node));
});
return result;
}
// Convert the tree back to an array of objects
const arrayFromTree = convertTreeToArray(tree);
console.log(arrayFromTree);

QM Helper

0 likes • Mar 22, 2022 • 1 view
JavaScript
//QM Helper by Leif Messinger
//Groups numbers by number of bits and shows their binary representations.
//To be used on x.com
const minterms = prompt("Enter your minterms separated by commas").split(",").map(x => parseInt(x.trim()));
const maxNumBits = minterms.reduce(function(a, b) {
return Math.max(a, Math.log2(b));
});
const bitGroups = [];
for(let i = 0; i < maxNumBits; ++i){
bitGroups.push([]);
}
for(const minterm of minterms){
let outputString = (minterm+" ");
//Count the bits
let count = 0;
for (var i = maxNumBits; i >= 0; --i) {
if((minterm >> i) & 1){
++count;
outputString += "1";
}else{
outputString += "0";
}
}
bitGroups[count].push(outputString);
}
document.body.textContent = "";
document.body.style.setProperty("white-space", "pre");
for(const group of bitGroups){
for(const outputString of group){
document.body.textContent += outputString + "\r\n";
}
}

Generate a random HEX color

0 likes • Nov 18, 2022 • 0 views
JavaScript
// Generate a random HEX color
randomColor = () => `#${Math.random().toString(16).slice(2, 8).padStart(6, '0')}`;
// Or
const randomColor = () => `#${(~~(Math.random()*(1<<24))).toString(16)}`;

kNearestNeighbors

0 likes • Nov 19, 2022 • 5 views
JavaScript
const kNearestNeighbors = (data, labels, point, k = 3) => {
const kNearest = data
.map((el, i) => ({
dist: Math.hypot(...Object.keys(el).map(key => point[key] - el[key])),
label: labels[i]
}))
.sort((a, b) => a.dist - b.dist)
.slice(0, k);
return kNearest.reduce(
(acc, { label }, i) => {
acc.classCounts[label] =
Object.keys(acc.classCounts).indexOf(label) !== -1
? acc.classCounts[label] + 1
: 1;
if (acc.classCounts[label] > acc.topClassCount) {
acc.topClassCount = acc.classCounts[label];
acc.topClass = label;
}
return acc;
},
{
classCounts: {},
topClass: kNearest[0].label,
topClassCount: 0
}
).topClass;
};
const data = [[0, 0], [0, 1], [1, 3], [2, 0]];
const labels = [0, 1, 1, 0];
kNearestNeighbors(data, labels, [1, 2], 2); // 1
kNearestNeighbors(data, labels, [1, 0], 2); // 0

luhnCheck implementation

0 likes • Nov 19, 2022 • 0 views
JavaScript
const luhnCheck = num => {
let arr = (num + '')
.split('')
.reverse()
.map(x => parseInt(x));
let lastDigit = arr.splice(0, 1)[0];
let sum = arr.reduce(
(acc, val, i) => (i % 2 !== 0 ? acc + val : acc + ((val *= 2) > 9 ? val - 9 : val)),
0
);
sum += lastDigit;
return sum % 10 === 0;
};
luhnCheck('4485275742308327'); // true
luhnCheck(6011329933655299); // true
luhnCheck(123456789); // false

compact object

0 likes • Nov 19, 2022 • 0 views
JavaScript
const compactObject = val => {
const data = Array.isArray(val) ? val.filter(Boolean) : val;
return Object.keys(data).reduce(
(acc, key) => {
const value = data[key];
if (Boolean(value))
acc[key] = typeof value === 'object' ? compactObject(value) : value;
return acc;
},
Array.isArray(val) ? [] : {}
);
};
const obj = {
a: null,
b: false,
c: true,
d: 0,
e: 1,
f: '',
g: 'a',
h: [null, false, '', true, 1, 'a'],
i: { j: 0, k: false, l: 'a' }
};
compactObject(obj);
// { c: true, e: 1, g: 'a', h: [ true, 1, 'a' ], i: { l: 'a' } }