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mean

Note

This is a point-in-time snapshot of the API documentation from January 2026. Going forward, we will not be maintaining a public copy of these references, and recommend users to refer to the built-in signature helpers available in the Hack LSP instead for complete and up-to-date information.

Returns the arithmetic mean of the numbers in the given container

namespace HH\Lib\Math;

function mean(
  Container<num> $numbers,
): ?float;
  • To find the sum, see Math\sum().
  • To find the maximum, see Math\max().
  • To find the minimum, see Math\min().

Parameters​

Returns​

  • ?float

Examples​

$v = vec[1, 2, 3, 4, 5];
$mean = Math\mean($v);
echo "Mean of the array is $mean \n"; // Output: Mean of the array is 3