max¶
- max(x: array, /, *, axis: int | Tuple[int, ...] | None = None, keepdims: bool = False) array ¶
Calculates the maximum value of the input array
x
.- Parameters:
x (array) – input array. Should have a real-valued data type.
axis (Optional[Union[int, Tuple[int, ...]]]) – axis or axes along which maximum values must be computed. By default, the maximum value must be computed over the entire array. If a tuple of integers, maximum values must be computed over multiple axes. Default:
None
.keepdims (bool) – if
True
, the reduced axes (dimensions) must be included in the result as singleton dimensions, and, accordingly, the result must be compatible with the input array (see Broadcasting). Otherwise, ifFalse
, the reduced axes (dimensions) must not be included in the result. Default:False
.
- Returns:
out (array) – if the maximum value was computed over the entire array, a zero-dimensional array containing the maximum value; otherwise, a non-zero-dimensional array containing the maximum values. The returned array must have the same data type as
x
.
Notes
When the number of elements over which to compute the maximum value is zero, the maximum value is implementation-defined. Specification-compliant libraries may choose to raise an error, return a sentinel value (e.g., if
x
is a floating-point input array, returnNaN
), or return the minimum possible value for the input arrayx
data type (e.g., ifx
is a floating-point array, return-infinity
).The order of signed zeros is unspecified and thus implementation-defined. When choosing between
-0
or+0
as a maximum value, specification-compliant libraries may choose to return either value.For backward compatibility, conforming implementations may support complex numbers; however, inequality comparison of complex numbers is unspecified and thus implementation-defined (see Complex Number Ordering).
Special Cases
For floating-point operands,
If
x_i
isNaN
, the maximum value isNaN
(i.e.,NaN
values propagate).
Changed in version 2023.12: Clarified that the order of signed zeros is implementation-defined.