round a number to the nearest thousandth in typescript

In TypeScript or JavaScript, you can use the toFixed() method to round a number to a specific number of decimal places. If you want to round a number to the nearest thousandth, you can pass 3 as the argument to toFixed() and then convert the resulting string back to a number using the parseFloat() function:

index.ts
const num = 1234.56789;
const roundedNum = parseFloat(num.toFixed(3));
console.log(roundedNum); // output: 1234.568
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Alternatively, you can use the Math.round() method in combination with a multiplication and division by powers of 10 to round to the nearest thousandth:

index.ts
const num = 1234.56789;
const roundedNum = Math.round(num * 1000) / 1000;
console.log(roundedNum); // output: 1234.568
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