#### Description:

This attribute gives the number of coordinate values required to specify an input point for a Mapping (i.e. the number of dimensions of the space in which the Mapping`’` s input points reside).

Type:

  Integer, read-only.

#### Applicability

##### Mapping

All Mappings have this attribute.

##### CmpMap

If a CmpMap`’` s component Mappings are joined in series, then its Nin attribute is equal to the Nin attribute of the first component (or to the Nout attribute of the second component if the the CmpMap`’` s Invert attribute is non-zero).

If a CmpMap`’` s component Mappings are joined in parallel, then its Nin attribute is given by the sum of the Nin attributes of each component (or to the sum of their Nout attributes if the CmpMap`’` s Invert attribute is non-zero).

##### Frame

The Nin attribute for a Frame is always equal to the number of Frame axes (Naxes attribute).

##### FrameSet

The Nin attribute of a FrameSet is equal to the number of axes (Naxes attribute) of its base Frame (as specified by the FrameSet`’` s Base attribute). The Nin attribute value may therefore change if a new base Frame is selected.
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