ExpScale

class ExpScale(a=2.718281828459045, b=1, c=1, inverse=False, minpos=1e-300, **kwargs)[source]

Bases: proplot.axistools._ScaleBase, matplotlib.scale.ScaleBase

“Exponential scale” that performs either of two transformations. When inverse is False (the default), performs the transformation

\[Ca^{bx}\]

where the constants \(a\), \(b\), and \(C\) are set by the input (see below). When inverse is True, this performs the inverse transformation

\[(\log_a(x) - \log_a(C))/b\]

which in appearence is equivalent to LogScale since it is just a linear transformation of the logarithm.

Parameters
  • a (float, optional) – The base of the exponential, i.e. the \(a\) in \(Ca^{bx}\).

  • b (float, optional) – The scale for the exponent, i.e. the \(b\) in \(Ca^{bx}\).

  • c (float, optional) – The coefficient of the exponential, i.e. the \(C\) in \(Ca^{bx}\).

  • minpos (float, optional) – The minimum permissible value, used to truncate negative values.

  • inverse (bool, optional) – If True, the “forward” direction performs the inverse operation.

Attributes Summary

name

The registered scale name.

Methods Summary

limit_range_for_scale(vmin, vmax, minpos)

Return vmin and vmax limited to positive numbers.