LogStretch¶

class astropy.visualization.LogStretch(a=1000.0)[source]¶

A log stretch.

The stretch is given by:

\[y = \frac{\log{(a x + 1)}}{\log{(a + 1)}}.\]

Parameters:	a : float The `a` parameter used in the above formula. Default is 1000.

Attributes Summary

inverse A stretch object that performs the inverse operation.

Methods Summary

__call__(values[, clip, out]) Transform values using this stretch.

Attributes Documentation

Methods Documentation

__call__(values, clip=True, out=None)[source]¶

Transform values using this stretch.

Parameters:	values : array-like The input values, which should already be normalized to the [0:1] range. clip : bool, optional If `True` (default), values outside the [0:1] range are clipped to the [0:1] range. out : `ndarray`, optional If specified, the output values will be placed in this array (typically used for in-place calculations).
Returns:	result : `ndarray` The transformed values.