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Oct 15, 2022CodeCatch
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Truncate to fixed decimal

Nov 19, 2022CodeCatch

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const toFixed = (n, fixed) => ~~(Math.pow(10, fixed) * n) / Math.pow(10, fixed);
// Examples
toFixed(25.198726354, 1); // 25.1
toFixed(25.198726354, 2); // 25.19
toFixed(25.198726354, 3); // 25.198
toFixed(25.198726354, 4); // 25.1987
toFixed(25.198726354, 5); // 25.19872
toFixed(25.198726354, 6); // 25.198726

drag and drop uploader

Nov 18, 2022AustinLeath

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const dragAndDropDiv = editor.container;
dragAndDropDiv.addEventListener('dragover', function(e) {
e.stopPropagation();
e.preventDefault();
e.dataTransfer.dropEffect = 'copy';
});
dragAndDropDiv.addEventListener("drop",function(e){
// Prevent default behavior (Prevent file from being opened)
e.stopPropagation();
e.preventDefault();
const files = e.dataTransfer.items; // Array of all files
console.assert(files.length >= 1);
if (files[0].kind === 'file') {
var file = e.dataTransfer.items[0].getAsFile();
const fileSize = file.size;
const fileName = file.name;
const fileMimeType = file.type;
reader = new FileReader();
reader.onloadend = function(){
editor.setValue(reader.result);
}
reader.readAsText(file);
}else{
//Maybe handle if text is dropped
console.log(files[0].kind);
}
});

kNearestNeighbors

Nov 19, 2022CodeCatch

0 likes • 5 views

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

typewriter-effect in Vanilla JS and React

Jan 25, 2023C S

0 likes • 7 views

// Vanilla JS Solution:
var app = document.getElementById('app');
var typewriter = new Typewriter(app, { loop: true });
typewriter
.typeString("I'm John and I'm a super cool web developer")
.pauseFor(3000)
.deleteChars(13) // "web developer" = 13 characters
.typeString("person to talk with!") // Will display "I'm John and I'm a super cool person to talk with!"
.start();
// React Solution:
import Typewriter from 'typewriter-effect';
<Typewriter
options={{ loop: true }}
onInit={typewriter => {
typewriter
.typeString("I'm John and I'm a super cool web developer")
.pauseFor(3000)
.deleteChars(13) // "web developer" = 13 characters
.typeString("person to talk with!") // Will display "I'm John and I'm a super cool person to talk with!"
.start();
}}
/>

Get timezone as a string

Nov 19, 2022CodeCatch

0 likes • 0 views

const getTimezone = () => Intl.DateTimeFormat().resolvedOptions().timeZone;
// Example
getTimezone();

Generate a random HEX color

Nov 18, 2022AustinLeath

0 likes • 1 view

// Or
const randomColor = () => `#${(~~(Math.random()*(1<<24))).toString(16)}`;
console.log(randomColor);