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Data Visualization (astropy.visualization)


astropy.visualization provides functionality that can be helpful when visualizing data. At the moment, functionalities include enhanced histograms, image normalizing (including both scaling and stretching), and custom plotting styles for matplotlib.


This module includes a command-line script, fits2bitmap to convert FITS images to bitmaps, including scaling and stretching of the image. To find out more about the available options and how to use it, type:

$ fits2bitmap --help


astropy.visualization.mpl_style Module

astropy.visualization Package


hist(x[, bins, ax]) Enhanced histogram function
quantity_support([format]) Enable support for plotting astropy.units.Quantity instances in matplotlib.
scale_image(image[, scale, power, asinh_a, ...]) Perform scaling/stretching of an image between minimum and maximum cut levels.


AsinhStretch An asinh stretch.
AsymmetricPercentileInterval(...[, n_samples]) Interval based on a keeping a specified fraction of pixels (can be asymmetric).
BaseInterval Base class for the interval classes, which, when called with an array of values, return an interval computed following different algorithms.
BaseStretch Base class for the stretch classes, which, when called with an array of values in the range [0:1], return an transformed array of values, also in the range [0:1].
BaseTransform A transformation object.
CompositeTransform(transform_1, transform_2) A combination of two transforms.
ContrastBiasStretch A stretch that takes into account contrast and bias.
HistEqStretch A histogram equalization stretch.
LinearStretch A linear stretch.
LogStretch A log stretch.
ManualInterval(vmin, vmax) Interval based on user-specified values.
MinMaxInterval Interval based on the minimum and maximum values in the data.
PercentileInterval(percentile[, n_samples]) Interval based on a keeping a specified fraction of pixels.
PowerDistStretch An alternative power stretch.
PowerStretch A power stretch.
SinhStretch A sinh stretch.
SqrtStretch A square root stretch.
SquaredStretch A convenience class for a power stretch of 2.

Class Inheritance Diagram

Inheritance diagram of astropy.visualization.stretch.AsinhStretch, astropy.visualization.interval.AsymmetricPercentileInterval, astropy.visualization.interval.BaseInterval, astropy.visualization.stretch.BaseStretch, astropy.visualization.transform.BaseTransform, astropy.visualization.transform.CompositeTransform, astropy.visualization.stretch.ContrastBiasStretch, astropy.visualization.stretch.HistEqStretch, astropy.visualization.stretch.LinearStretch, astropy.visualization.stretch.LogStretch, astropy.visualization.interval.ManualInterval, astropy.visualization.interval.MinMaxInterval, astropy.visualization.interval.PercentileInterval, astropy.visualization.stretch.PowerDistStretch, astropy.visualization.stretch.PowerStretch, astropy.visualization.stretch.SinhStretch, astropy.visualization.stretch.SqrtStretch, astropy.visualization.stretch.SquaredStretch

astropy.visualization.mpl_normalize Module

Normalization class for Matplotlib that can be used to produce colorbars.


ImageNormalize([vmin, vmax, stretch, clip]) Normalization class to be used with Matplotlib.

Class Inheritance Diagram

Inheritance diagram of astropy.visualization.mpl_normalize.ImageNormalize