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Where

Select from one or another array elementwise, depending on an elementwise condition mask.

Generally, the mask, where_true and where_false data should be of the same shape, though where_true and where_false can also be single values in which case that value will be used for each matching value in the mask, or vectors in which case the vector will be broadcast to the shape of the mask. If the where_true and where_false inputs are of different types, the result result will be of the highest type (highest to lowest: Packet, array, list, float, int). This node is functionally equivalent to the "where" operator of the Python Array API (see link) and returns values and not the indices of matching values (like numpy.where(condition)). If the latter is desired (for example, to get the indices of values to then select using SelectRange), use the ArrayNonzero node instead. More Info... Version 1.0.0

Ports/Properties

mask

Condition mask.

verbose name
Mask
default value
None
port type
DataPort
value type
AnyNumeric (can be None)
data direction
IN

where_true

Data to choose from where condition is true.

verbose name
Where True
default value
None
port type
DataPort
value type
AnyNumeric (can be None)
data direction
IN

where_false

Data to choose from where condition is false.

verbose name
Where False
default value
None
port type
DataPort
value type
AnyNumeric (can be None)
data direction
IN

result

Output data.

verbose name
Result
default value
None
port type
DataPort
value type
AnyNumeric (can be None)
data direction
OUT

missing

Behavior when the true or false arrays are None.

verbose name
Missing
default value
error
port type
EnumPort
value type
str (can be None)

set_breakpoint

Set a breakpoint on this node. If this is enabled, your debugger (if one is attached) will trigger a breakpoint.

verbose name
Set Breakpoint (Debug Only)
default value
False
port type
BoolPort
value type
bool (can be None)

metadata

User-definable meta-data associated with the node. Usually reserved for technical purposes.

verbose name
Metadata
default value
{}
port type
DictPort
value type
dict (can be None)

axis_pairing

How to pair axes of the operands. In 'positional' mode, axes are paired by their position according to a right alignment, that is, the last axis of the first operand is paired with the last axis of the second operand, and so on, while any missing axes behave as if they were unnamed axes of length 1 (this is the same way plain n-dimensional arrays pair in Python/numpy). In 'matched' mode, axes are paired by their type and optionally label, where the axis order of the first operand is preserved in the output, optionally with additional axes that only occur in the second operand prepended on the left. The other operand then has its axes reordered to match. All axis classes are treated as distinct, except for the plain axis, which is treated as a wildcard axis that can pair with any other axis. The 'default' value resolves to a value that may be overridden in special contexts (mainly the ambient Inference node) and otherwise resolves to the setting of the configuration variable default_axis_pairing, which is set to 'positional' in 2024.x. See also the 'label_handling' property for how labels are treated in this mode. Note that axis pairing can be subtle, and it is recommended to not blindly trust that the default behavior is always what the user intended.

verbose name
Axis Pairing
default value
default
port type
EnumPort
value type
str (can be None)

label_pairing

How to treat axis labels when pairing axes in 'matched' mode. In 'always' mode, labels are always considered significant, and axes with different labels are always considered distinct, which means that, if the two operands each have an axis of same type but with different labels, each operand will have a singleton axis inserted to pair with the respective axis in the other operand. In 'ignore' mode, labels are entirely ignored when pairing axes; this means that, if multiple axes of the same type occur in one or more operands, the last space axis in the first operand is paired with the last space axis in the second operand, etc. as in positional mode. In 'auto' mode, labels are only considered significant if they are necessary for distinguishing two or more axes of the same type in any of the operands, or if they occur on a plain axis.

verbose name
Label Pairing
default value
auto
port type
EnumPort
value type
str (can be None)

lists_as_arrays

Whether to treat lists as numeric arrays, as opposed to a recursive data structure. This is equivalent to converting any list operand(s) to arrays before passing them to the node. Broadly, enabling this allows for more efficient processing of large lists of either numbers, or lists of many smaller arrays, with some limitations and caveats, as follows. If one operand was a list and the other an array, an array will be returned, and if all were lists, a list will be returned (if the operand lists themselves contained arrays, the result is still a "pure" list of potentially nested lists of numbers). A limitation is that input lists may contain ONLY numbers or arrays of the same shape (e..g., no lists of blocks or packets, dictionaries, or irregular array shapes in this mode). In contrast, when the option is disabled, then if one operand is a list and the other is not a list (e.g., a number, array, block, packet, etc), then each element of the list is separately undergoing the operation while the other operand is held fixed. This has the consequence that a) the result will generally be a list if at least one operand is a list and b) the result will be mathematically different when one is a list and the other is an array, because the array will be separately combined with each list element. Note the default for this option was enabled by default in NeuroPype 2023. The option can also be set globally or in a context using the WithOptions node, for example for pipeline-wide backwards compatibility.

verbose name
Lists As Arrays
default value
False
port type
BoolPort
value type
bool (can be None)