The Math.max()
function returns the largest of the zero or more numbers given as input parameters.
Math.max([value1[, value2[, ...]]])
value1, value2, ...
The largest of the given numbers. If any of the arguments are NaN
or cannot be converted to a number, NaN
is returned.
Because Math
is not a constructor, max()
is a static method of Math
(You always use it as Math.max()
, rather than as a method of an instanced Math
object).
-Infinity
is the initial comparant because it is smaller than all other numbers, so that's why when no arguments are given, -Infinity
is returned.
If any of the arguments are NaN
or cannot be converted to a number, the result is NaN
.
Math.max(10, 20); // 20 Math.max(-10, -20); // -10 Math.max(-10, 20); // 20
Array.reduce()
can be used to find the maximum element in a numeric array, by comparing each value:
var arr = [1,2,3]; var max = arr.reduce(function(a, b) { return Math.max(a, b); });
The following function uses Function.prototype.apply()
to get the maximum of an array. getMaxOfArray([1, 2, 3])
is equivalent to Math.max(1, 2, 3)
, but you can use getMaxOfArray()
on programmatically constructed arrays. This should only be used for arrays with relatively few elements.
function getMaxOfArray(numArray) { return Math.max.apply(null, numArray); }
The new spread operator is a shorter way of writing the apply
solution to get the maximum of an array:
var arr = [1, 2, 3]; var max = Math.max(...arr);
However, both spread (...
) and apply
will either fail or return the wrong result if the array has too many elements, because they try to pass the array elements as function parameters. See Using apply and built-in functions for more details. The reduce
solution does not have this problem.
Desktop | ||||||
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max |
1 | 12 | 1 | 3 | 3 | 1 |
Mobile | ||||||
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max |
1 | 18 | 4 | 10.1 | 1 | 1.0 |
Server | |
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max |
0.1.100 |
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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://wiki.developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math/max