Description:
For each
data point this routine places it into a bin in the output grid depending on the position of the
data point on the sky. The position in the input data array is stored. This is done in two
stages:
-
Find the size of the output grid from the maximum extent of the input data.
-
Loop through data. Find I,J coordinate of each point in the output grid.
-
Find out maximum number of points for an I,J position.
-
Put data onto grid in array (I,J,N) [REALS]. We also need to store positions of these data. We can either
do it by storing the file number, bolometer and position (time) index OR we can just store some index
in a merged data array that goes from 1..TOT_PTS. First method is easy but memory hungry. Second
method is more efficient but does need some reconstruction to work out where the point was in the
original data. Use the second method.
Once the data is gridded, it is first displayed and then despiked. Currently despiking is done on a
simple sigma clipping basis for each bin.
Invocation
CALL SURF_GRID_DESPIKE ( N_FILES, N_PTS,
N_POS, N_BOLS, WAVELENGTH, DIAMETER, BOL_RA_PTR, BOL_DEC_PTR, DATA_PTR, QUALITY_PTR,
NX, NY, ICEN, JCEN, NSPIKES, BADBIT, STATUS )
Arguments
N_FILES = INTEGER (Given)
Number of data sets (ie files)
N_PTS ( N_FILES ) = INTEGER (Given)
Total number of points
in each map
N_POS( N_FILES ) = INTEGER (Given)
Number of positions per set (Y
positions)
N_BOLS( N_FILES ) = INTEGER (Given)
Number of bolometers per set (X
positions)
BITNUM = INTEGER (Given)
Bit number to be affected by this routine
WAVELENGTH = REAL (Given)
Wavelength of data (microns)
DIAMETER = REAL (Given)
Diameter of telescope (metres)
BOL_RA_PTR( N_FILES ) = INTEGER (Given)
Array of
pointers to position information (X coords) Note that each data set has positions for N_POS
N_BOLS
BOL_RA_PTR( N_FILES ) = INTEGER (Given)
Array of pointers to position information
(Y coords)
DATA_PTR( N_FILES ) = INTEGER (Given)
Pointers to actual data arrays
QUALITY_PTR( N_FILES ) = INTEGER (Given)
Pointer to quality arrays
NX = INTEGER
(Returned)
Number of points in grid (X)
NY = INTEGER (Returned)
Number of points in grid (Y)
ICEN = INTEGER (Returned)
Reference pixel (X)
JCEN = INTEGER (Returned)
Reference pixel
(Y)
NSPIKES ( N_FILES ) = INTEGER (Returned)
Number of spikes detected (and removed) in
each file
BADBIT ( N_FILES ) = BYTE (Given)
Bad bit mask for identifying bad pixels
from quality
STATUS = INTEGER (Given & Returned)
Global Status
Notes:
For
SMODE=NONE, DMODE is only requested if a plot is required.
Copyright
Copyright
©1995,1996,1997,1998,1999 Particle Physics and Astronomy Research Council. All Rights Reserved.