YTPLANE-Adds contiguous YT planes of a data cube to form an image

Description:

Given a data cube (strictly a cuboid) YTPLANE extracts a 2-D image from it by adding together a number of planes of constant X.

Parameters:

CUBE

The name of a 3-dimensional data cuboid, from which YTPLANE is to extract a 2-D image by adding together contiguous planes of constant X value, the X dimension being the first dimension of the data.

XSTART

The X value of the first of the planes to be added together to form the extracted image. If the X axis of the cube is calibrated, XSTART must be specified in the units in which it is calibrated. Otherwise, the element number (1..N) should be used.

XEND

The X value of the last of the planes to be added together to form the extracted image.

IMAGE

The name of the 2-D image to be created by YTPLANE.

Source comments:

 Y T P L A N E ,   X T P L A N E,    X Y P L A N E

 Adds a number of consecutive planes from a cube to
 produce a 2-D data object.  YTPLANE, XTPLANE and XYPLANE
 take planes whose X,Y or T values respectively are
 constant over the extracted plane.  (Pedantic note:
 strictly, a cuboid is meant, rather than a cube.)
 (Further pedantic note: the X, Y and T axes
 mentioned in this routine should really be referred to
 as AXIS(1), AXIS(2) and AXIS(3) respectively. However,
 explanations become confusing if this is done, so the references to
 X, Y and T remain. This does not mean that the data is stored in
 .X .Y and .T structures - JM.)

 Command parameters -

 'CUBE'     The name of the cube from which the planes
            are to be taken.

 'XSTART'   The X,Y, or T-value of the first plane to be used.
 'YSTART'   If CUBE has a X, Y or T  structure, the data
 'TSTART'   from this is used.  If not, the plane numbers
            are used, starting from 1.

 'XEND'     The X, Y, or T-value of the last plane to be used.
 'YEND'
 'TEND'

 'IMAGE'    The name of the resulting data structure.

 Input data -

 CUBE - 3-D data-array

 Output data -

 IMAGE is created with the same structure as CUBE
 except that the data array will only have 2 dimensions, and if
 CUBE has a X,Y or T structure, this will be omitted -
 that is, XPLANE will omit any X structure, YPLANE any
 Y structure and  etc.
                                 KS / AAO 8th Jan 1985