Math.ceil():無條件進位
Math.ceil(3.14) // 4 Math.ceil(5.4) // 6 Math.ceil(-5.4) // -5(注意:負數時無條件捨去) Math.ceil("-5.5") // -5(注意:負數時無條件捨去)
Math.imul(3, 4);//12 Math.imul(-5, 12);//-60
var myArray1 = [1, 5, 6, 2, 3]; var min1 = Math.min(...myArray1); //console.log(min1), //1 var myArray2 = [1, 5, 6, 2, 3]; var min2 = Math.min.apply(null, myArray2); console.log(min2) //1 function MyMin(myarr){ var al = myarr.length; minimum = myarr[al-1]; while (al--){ if(myarr[al] < minimum){ minimum = myarr[al] } } return minimum; }; var myArray3 = [1, 5, 6, 2, 3]; var min3 = MyMin(myArray3); console.log(min3)
Math.pow(x,y)=Xy
x:基數
y:指數
console.log(Math.pow(7, 3)); // Expected output: 343 console.log(Math.pow(4, 0.5)); // Expected output: 2 console.log(Math.pow(7, -2)); // Expected output: 0.02040816326530612 // (1/49) console.log(Math.pow(-7, 0.5)); // Expected output: NaN
function getCircleY(radians, radius) { return Math.sin(radians) * radius; } console.log(getCircleY(1, 10)); // Expected output: 8.414709848078965 console.log(getCircleY(2, 10)); // Expected output: 9.092974268256818 console.log(getCircleY(Math.PI, 10)); // Expected output: 1.2246467991473533e-15
Math.sqrt(x)=√ ̄=the unique y>=0 such that y2=x
function calcHypotenuse(a, b) { return (Math.sqrt((a * a) + (b * b))); } console.log(calcHypotenuse(3, 4)); // Expected output: 5 console.log(calcHypotenuse(5, 12)); // Expected output: 13 console.log(calcHypotenuse(0, 0)); // Expected output: 0
//方法會傳回一個新字串,此新字串是透過將原字串與 pattern 比對,以 replacement 取代吻合處而生成
const p = 'The quick brown fox jumps over the lazy dog. If the dog reacted, was it really lazy?'; const p const pReplace=p.replace('dog', 'monkey'); console.log('Preplace',pReplace); //"The quick brown fox jumps over the lazy monkey. If the dog reacted, was it really lazy?"
const p = 'The quick brown fox jumps over the lazy dog. If the dog reacted, was it really lazy?'; const pReplaceAll=p.replaceAll('dog', 'monkey'); console.log('PreplaceAll',pReplaceAll); //"The quick brown fox jumps over the lazy monkey. If the monkey reacted, was it really lazy?" const regex = /Dog/ig; console.log(p.replaceAll(regex, 'ferret')); //"The quick brown fox jumps over the lazy ferret. If the ferret reacted, was it really lazy?"