FILLCUBE-Copy one NDF into part of another.

Usage:

fillcube in out

Description:

This routine copies data, variance etc. from one NDF into another existing NDF. By successive calls the output NDF can be filled with data from a number of input NDFs. The target area in the output is identified by matching axis data (not pixel indices). Data are copied from input to output only if the input data value is not bad, apart from that existing data in the output are overwritten.

Parameters:

INFO

INFO = _LOGICAL (Read) True if informational messages are to be issued.

TOL

TOL = _REAL (Read) The tolerated fraction of the pixel size by which the input coordinates may deviate from the output coordinates. If any one of the axis values deviates more than TOL times the coordinate step, then the input data are ignored and the output data left unchanged. [0.2]

IN

IN = NDF (Read) The input NDF.

OUT

OUT = NDF (Read) The output NDF. This must already exist, update access is required.

Source comments:

   F I L L C U B E

   This application is more akin to ASCIN than to GROW. The main
   differences to ASCIN are that FILLCUBE updates an existing output
   and that its input is an NDF rather than an ASCII table.
   Its main advantage over GROW is that input and output may
   (actually must) have the same dimensionality, but any dimensions
   or axis data can differ. Also it is not necessary that target
   pixels form a contiguous subset in the output: The input pixels
   could match, say, every second or third output pixel.
   The disadvantages are that results and spectroscopic values in the
   Specdre Extension are not handled, and that the coordinates along
   each axis in input and output must be linear.

   For each input pixel, FILLCUBE looks for the output pixel that is
   nearest in the space of axis data coordinates. Data are copied
   only if the output pixel is hit close to its centre. However, if
   an axis is degenerate (has only one pixel) in both input and
   output, then the coordinates are assumed to match.

   No indication is given as to how many input pixels did not match
   any output pixel.

Notes:

This routine recognises the Specdre Extension v. 0.7, although it is largely ignored.

This routine works in situ on an existing output file.

Spectroscopic values must not exist in the Extension of either the input or the output NDF: A unique coordinate axis is required for all axes, including the spectroscopic one, in order to locate the target pixels by matching coordinates between input and output. If this is inconvenient, GROW may be a more suitable application for your purpose.

Spectroscopic widths must not exist in the Extension of the output NDF and are ignored in the input NDF: This information is likely to be present only when spectroscopic values are present as well.

Covariance row sums must not exist in the Extension of the output NDF: The validity of this information is difficult to assess when only parts of spectra might be copied from one cube to another, and when these parts are contiguous in the input but might not be in the output. Input covariance row sums are ignored.

The results in the input Extension are ignored, and results must not exist in the output Extension.