gwcs.wcstools.grid_from_bounding_box

gwcs.wcstools.grid_from_bounding_box(bounding_box, step=1, center=True, selector=None)

Create a grid of input points from the WCS bounding_box.

Note: If bbox is a tuple describing the range of an axis in bounding_box,

x.5 is considered part of the next pixel in bbox[0] and part of the previous pixel in bbox[1]. In this way if bbox describes the edges of an image the indexing includes only pixels within the image.

The bounding_box is in order of X, Y [, Z] and the output will be in the same order.

Parameters:

• bounding_box (tuple | ModelBoundingBox | CompoundBoundingBox) – The bounding_box of a WCS object, bounding_box.

• step (scalar or tuple) – Step size for grid in each dimension. Scalar applies to all dimensions.

• center (bool) – If True use the center of the pixel, otherwise use the corner.

• selector (tuple | None) – If selector is set then it must be a selector tuple and bounding_box must be a CompoundBoundingBox.

Examples

>>> bb = ((-1, 2.9), (6, 7.5))
>>> grid_from_bounding_box(bb, step=(1, .5), center=False)
array([[[-1. ,  0. ,  1. ,  2. ,  3. ],
        [-1. ,  0. ,  1. ,  2. ,  3. ],
        [-1. ,  0. ,  1. ,  2. ,  3. ],
        [-1. ,  0. ,  1. ,  2. ,  3. ]],
       [[ 6. ,  6. ,  6. ,  6. ,  6. ],
        [ 6.5,  6.5,  6.5,  6.5,  6.5],
        [ 7. ,  7. ,  7. ,  7. ,  7. ],
        [ 7.5,  7.5,  7.5,  7.5,  7.5]]])

>>> bb = ((-1, 2.9), (6, 7.5))
>>> grid_from_bounding_box(bb)
array([[[-1.,  0.,  1.,  2.,  3.],
        [-1.,  0.,  1.,  2.,  3.]],
       [[ 6.,  6.,  6.,  6.,  6.],
        [ 7.,  7.,  7.,  7.,  7.]]])

Returns:

x, y [, z] – Grid of points.

Return type:

ndarray