Coordinates

class glue.core.coordinates.Coordinates

Bases: object

Base class for coordinate transformation

Methods Summary

axis_label(self, axis)
default_world_coords(self, ndim)
dependent_axes(self, axis)	Return a tuple of which world-axes are non-independent from a given pixel axis
pixel2world(self, \*args)	Convert pixel to world coordinates, preserving input type/shape.
pixel2world_single_axis(self, \*pixel, …)	Convert pixel to world coordinates, preserving input type/shape.
world2pixel(self, \*args)	Convert world to pixel coordinates, preserving input type/shape.
world2pixel_single_axis(self, \*world, …)	Convert world to pixel coordinates, preserving input type/shape.
world_axis(self, data, axis)	Find the world coordinates along a given dimension, and which for now we center on the pixel origin.
world_axis_unit(self, axis)	Return the unit of the world coordinate given by axis (assuming the Numpy axis order)

Methods Documentation

axis_label(self, axis)

default_world_coords(self, ndim)

dependent_axes(self, axis)

Return a tuple of which world-axes are non-independent from a given pixel axis

The axis index is given in numpy ordering convention (note that opposite the fits convention)

pixel2world(self, *args)

Convert pixel to world coordinates, preserving input type/shape.

Parameters

*pixelscalars lists, or Numpy arrays

The pixel coordinates (0-based) to convert

Returns

*worldNumpy arrays

The corresponding world coordinates

pixel2world_single_axis(self, *pixel, **kwargs)

Convert pixel to world coordinates, preserving input type/shape.

This is a wrapper around pixel2world which returns the result for just one axis, and also determines whether the calculation can be sped up if broadcasting is present in the input arrays.

Parameters

*pixelscalars lists, or Numpy arrays

The pixel coordinates (0-based) to convert

axisint, optional

If only one axis is needed, it should be specified since the calculation will be much more efficient.

Returns

worldnumpy.ndarray

The world coordinates for the requested axis

world2pixel(self, *args)

Convert world to pixel coordinates, preserving input type/shape.

Parameters

*worldscalars lists, or Numpy arrays

The world coordinates to convert

Returns

*pixelNumpy arrays

The corresponding pixel coordinates

world2pixel_single_axis(self, *world, **kwargs)

Convert world to pixel coordinates, preserving input type/shape.

This is a wrapper around world2pixel which returns the result for just one axis, and also determines whether the calculation can be sped up if broadcasting is present in the input arrays.

Parameters

*worldscalars lists, or Numpy arrays

The world coordinates to convert

axisint, optional

If only one axis is needed, it should be specified since the calculation will be much more efficient.

Returns

pixelnumpy.ndarray

The pixel coordinates for the requested axis

world_axis(self, data, axis)

Find the world coordinates along a given dimension, and which for now we center on the pixel origin.

Parameters

data~glue.core.data.Data

The data to compute the coordinate axis for (this is used to determine the size of the axis)

axisint

The axis to compute, in Numpy axis order

Notes

This method computes the axis values using pixel positions at the center of the data along all other axes. This will therefore only give the correct result for non-dependent axes (which can be checked using the dependent_axes method).

world_axis_unit(self, axis)

Return the unit of the world coordinate given by axis (assuming the Numpy axis order)