29
Numerics library
[numerics]
29.6
Numeric arrays
[numarray]
29.6.8
Class template
mask_
array
[template.mask.array]
29.6.8.1
Overview
[template.mask.array.overview]
🔗
namespace
std
{
template
<
class
T
>
class
mask_array
{
public
:
using
value_type
=
T;
void
operator
=
(
const
valarray
<
T
>
&
)
const
;
void
operator
*
=
(
const
valarray
<
T
>
&
)
const
;
void
operator
/
=
(
const
valarray
<
T
>
&
)
const
;
void
operator
%
=
(
const
valarray
<
T
>
&
)
const
;
void
operator
+
=
(
const
valarray
<
T
>
&
)
const
;
void
operator
-
=
(
const
valarray
<
T
>
&
)
const
;
void
operator
^
=
(
const
valarray
<
T
>
&
)
const
;
void
operator
&
=
(
const
valarray
<
T
>
&
)
const
;
void
operator
|
=
(
const
valarray
<
T
>
&
)
const
;
void
operator
<
=
(
const
valarray
<
T
>
&
)
const
;
void
operator
>
=
(
const
valarray
<
T
>
&
)
const
; mask_array
(
const
mask_array
&
)
;
~
mask_array
(
)
;
const
mask_array
&
operator
=
(
const
mask_array
&
)
const
;
void
operator
=
(
const
T
&
)
const
; mask_array
(
)
=
delete
;
/ as implied by declaring copy constructor above
}
;
}
1
#
This template is a helper template used by the mask subscript operator:
🔗
mask_array
<
T
>
valarray
<
T
>
::
operator
[
]
(
const
valarray
<
bool
>
&
)
;
2
#
It has reference semantics to a subset of an array specified by a boolean mask
.
Thus, the expression
a
[
mask
]
=
b;
has the effect of assigning the elements of
b
to the masked elements in
a
(those for which the corresponding element in
mask
is
true
)
.