﻿ ﻿JavaScript Math - JAVASCRIPT: A Beginner’s Guide to Learning the Basics of JavaScript Programming (2015)

# JAVASCRIPT: A Beginner’s Guide to Learning the Basics of JavaScript Programming (2015)

### Chapter 18. JavaScript Math

Math is a built-in object in JavaSript, which has methods and properties for math functions and constants, but not a function object. Math is not considered a constructor in JavaScript, unlike other global objects. The methods and properties of JS Math are static. We can consider the constant pi as Math.PI; we can refer to the sine as Math.sin(x). Take note that the X refers to the argument of the method. In JavaScript, constants are prescribed with complete precision, thanks to real numbers (as opposed to integers).

Properties of Math in JS

Refer to the table below for the different math properties used in JavaScript

 Properties Description Math.E The Euler’s Constant, which is the base of natural logs, about 2.718 Math.LN10 The natural log of 10, about 2.303 Math.LN2 The natural log of 2, about 0.693 Math.LOG10E Base 10 log of E, about 0.434 Math.LOG2E Base 2 log of E, about 1.443 Math.SQRT2 Sq. root of 2, about 1.414 Math.SQRT1_2 Sq.root of ½ eq, 1 / sq. 2, about 0.707 Math.PI Ratio of circle circum to the diam about 3.1415

Methods

Take note that the trigo functions (atan2(), atan(), acos(), asin(), tan(), cos(), sin()) return radians angles. In order to conv radians into degrees, you can divide using Math.PI and multiply it for reverse conversion.

In addition, the precision of math functions in JS are dependent on implementation. Hence, various browsers will yield varying results. Even similar engines on a different architecture or operating system may yield varying results.

Refer to the table below for the different Math Methods in JS

 Methods Math. Description .abs(x) Yields the absolute number value .acosh(x) Yields the number’s hyperbolic arcosine. .acos(x) Yields the number’s arcosine .asinh(x) Yields the number’s hyperbolic arcsine .asin(x) Yields the number’s arcsine .atanh(x) Yields the number’s hyperbolic arctangent .atan(x) Yields the number’s arctangent .atan2(x, y) Yields the quotient’s arctangent arguments .cbrt(x) Yields the number’s cube root .clz32(x) Yields the number prime zeros of a 32-bit int .ceil(x) Yields the min integer >= to x .cos(x) Yields the number’s cosine .coshh(x) Yields the number’s hyperbolic cosine .exp(x) Yields Ex (x=argument, E=Euler’s constant (log base) .floor(x) Yields the biggest int <= to x .fround(x) Yields the number’s nearest single precision float rep .hypot(x) Yields the sq root of the sum of sq of args .imul(x,y) Yields the result of multiplying 32-bit int .log(x) Yields the number’s natural log .log2(x) Yields the number’s base 2 log .log1p(x) Yields the number’s natural log of 1+x .log10(x) Yields the number’s base 10 log .max([x[,y[,-]]]) Yields the biggest zero or more numbers .min([x[,y[,-]]]) Yields the min zero or more numbers .pow(x. y) Yields base to exp power .random Yields a pseudo-random number between zero and 1 .sign(x) Yields the sign of the number, which indicates if x is zero, negative, or positive .round(x) Yields the number’s value rounded to the nearest int .sin(x) Yields the number’s sine .sinh(x) Yields the number’s hyperbolic sine .sqrt(x) Yields the number’s positive sq root .tan(x) Yields the number’s tangent .tanh(x) Yields the number’s hyperbolic tangent .trunc(x) Yields the number’s integral part, which removes any fractional digits

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