Introduction to JavScript math max() method
Comparison is at the heart of “almost” everything we do, and with numerical values, they are needed to carry out certain operations. We need to know the maximum or the minimum value within a sequence or series of numbers for certain applications.
Say, we need to know what value was the highest or smallest within our
dataset, we need a function or method that does just that. Luckily for
us, JavaScript provides a Math object that allows us to achieve this,
and more specifically, we can find the highest or largest value using
the Math max method.
In this article, we will discuss ways to use the JavaScript Math max
method
Using the Math max() method
As stated earlier, the Math.max() method returns the largest of the
series of numbers that are passed as an argument. Using the Math max
method, we can try three approaches - normal arguments, the reduce
method and the spread operator - to make use of the Math max method.
Using normal arguments
We can pass all the numbers we want to compare to the Math.max method
to find the highest or largest value among them
console.log(Math.max(12, 3, 4, 5, 67, 321, 121212));
Output
121212
Though this is simple, it can be unrealistic when dealing with a large
set of numbers probably stored within an array, and that’s where the
spread operator comes in.
Using the spread operator
The spread operator allows expanding all the elements of an iterable
such as an array as arguments to functions. So, with these, we can pass
all the elements of the array to the Math.max function.
const arr = [
12, 34, 56, 7, 121, 12212, 12, 2345, 34565, 454, 343, 3432, 778, 454,
];
const highElement = Math.max(...arr);
console.log(highElement);
Output
34565
Using reduce method
The reduce method is a higher-order function that takes a callback
function that works on each element where an operation is done in
relation to the preceding element to result in a single value. So in our
case, the operation that will be done will be the Math.max() method
call.
To illustrate, we will apply the Math.max() method on the current
element and its preceding element by find the highest value between the
two values via the reduce method till we return the highest across all
the elements in the array.
const arr = [
12, 34, 56, 7, 121, 12212, 12, 2345, 34565, 454, 343, 3432, 778, 454,
];
const max = arr.reduce((a, b) => Math.max(a, b));
console.log(max);
Output
34565
So, instead of using the spread operator, we use the reduce method
to apply the Math.max() method on two numbers (the preceding highest
element, and the current element) at a time. Note that at the start of
the reduce method, the preceding element is -Infinity which is
considered the lowest number automatically (we can define it in our
expression statement but it’s optional).
Summary
The Math.max method is a good JavaScript method that allows us to find
the highest or largest number value among a series of numeric values and
can be approached by using the parameters, the spread operator, and
the reduce method.
References
Math.max() - JavaScript | MDN
(mozilla.org)
Spread syntax (…) - JavaScript | MDN
(mozilla.org)
Array.prototype.reduce() - JavaScript |
MDN (mozilla.org)
