pp_simple_scale — Column-wise min–max scaling to [0, 1]¶
Group: Preprocessing · C ABI: n4m_transform_simple_scale_*
Description¶
Column-wise min-max scaling to [0, 1].
Parameters¶
No constructor parameters.
API and bindings¶
C ABI (ABI 2): n4m_transform_simple_scale_create · n4m_transform_simple_scale_destroy · n4m_transform_simple_scale_transform. Use the linked public header for the exact signature, configuration, and result handles.
Python (verified public re-export):
from n4m.transform.scaling import SimpleScale
Source signature: SimpleScale().
R: no current source-verified entry point was found for this catalog method.
MATLAB / Octave: no current source-verified entry point was found for this catalog method.
Explanations¶
Bibliographic source¶
No canonical paper: this is the affine min–max transform \((x_j-\min x_j)/(\max x_j-\min x_j)\).
Mathematical principle¶
For each column, the operation computes its minimum and maximum over the supplied rows and maps the extrema to zero and one, respectively.
Appropriate uses¶
Putting wavelength variables on a common bounded numeric scale before distance- or regularization-sensitive procedures.
Limits and validation¶
Extrema are outlier-sensitive and, in this stateless operation, are recomputed on each input matrix rather than retained from training. Constant columns require guarded handling and absolute spectral scale is lost.
Implementation¶
n4m.transform.scaling.SimpleScale uses n4m_transform_simple_scale_*; column extrema and affine scaling are in preprocessing/scaling/simple_scale.c.
The ABI-2 implementation is the n4m_transform_simple_scale_* lifecycle in libn4m.
Sources and provenance¶
See also: methods index · interactive dashboard