Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.atnf.csiro.au/computing/software/gipsy/tsk/cursor.dc1 Дата изменения: Tue Aug 1 09:47:11 2000 Дата индексирования: Fri Jan 16 01:12:03 2009 Кодировка: Поисковые слова: система координат галактическая

Program: CURSOR

Purpose: Write positions (GRIDS and PHYSICAL coordinates), pointed
with an interactive graphics cursor in a GIDS overlay, to
screen or ASCII file. Write also (interpolated) image
values.

Category: UTILITY

File: cursor.c

Author: M.G.R. Vogelaar

Keywords:


INSET= Give input set (, subsets):

If there is not a set displayed on GIDS then you are
prompted with this keyword. The task VIEW will be
spawned to display the map.
Maximum number of subsets is 2048.


BOX= Give box in ..... [entire subset]


**COLOUR= Marker colour (number or abbrv. name): [red]

The positions pointed by the graphics cursor will
be marked in this colour. The colour is entered as
a number between 1 and 15 (see notes) or as a string
which represent a colour. The colours are listed in
the description. Colour strings can be abbreviated.
Example: Set marker colour to yellow:
COLOUR=7
COLOUR=Yellow
COLOUR=yel


FILENAME= Give name of ASCII file: [No file]

Write positions to a file on disk or screen. If a
transformation to physical coordinates is possible,
write these coordinates also.


OVERWRITE= File exists, ok to overwrite? [Y]/N

Only prompted if FILENAME= is an existing file.



Description: Program CURSOR writes an ASCII table with positions
pointed with a graphics cursor in GIDS where a (sub)set
is loaded. If nothing is loaded or GIDS is not available
you are prompted with the INSET= and the BOX= keywords.
Then application VIEW is spawned and (after VIEWs'
CLIP= keyword) a (sub)set is loaded. A simple frame
is plotted and the graphics cursor appears.

With the cursor it is possible to select positions with
the left button or any keyboard key except 'Q'/'q'. The
cursor loop is aborted if the right mouse button or the
keyboard key 'Q' (or 'q') is pressed.

Default, the entered positions are written to screen,
but if you give a name at the FILENAME= prompt,
the data is written to an ASCII file on disk.

The first column in the file (or on screen) is a grid
position in X direction, the second is a grid position
in Y direction. If a transformation to header units is
possible, then also these transformed physical coordinates
are written where both columns are prefixed with a 'U' to
indicate that the units are header units (in most cases:
DEGREE). Between grid- and physical coordinates is a column
with the interpolated image value at the listed position.
Image data is taken from the input set at the four integer
neighbouring positions of an input position. If all
positions are within the input box (BOX=) and all image
data is not blank then a bilinear interpolation is applied.
For three valid neighbours, a plane is constructed to do
the interpolation and for two positions, the interpolation
is linear.
Example of the output:

User : M.G.R. Vogelaar
Date of creation : Thu Jan 4 16:51:31 1996
X-grid Y-grid Image X-physical Y-physical
=================================================================
-18.44 -19.94 +0.76 U +158.346481 U -39.386364
-12.19 -19.56 -0.00 U +158.312785 U -39.384825
-5.31 -24.81 +0.36 U +158.275732 U -39.406715
etc.

The prefix 'U' indicates that the coordinates are expressed
in units as found in the header of INSET=.


The colours that can be used are:

index name
=============================================
0 Background
1 Default (Black if background is white)
2 Red
3 Green
4 Blue
5 Cyan
6 Magenta
7 Yellow
8 Orange
9 Green + Yellow
10 Green + Cyan
11 Blue + Cyan
12 Blue + Magenta
13 Red + Magenta
14 Dark Gray
15 Light Gray


Notes: If you started GIDS on another machine than the one on
which you run CURSOR, then cursor actions can be very slow!

Example: .......

Updates: Feb 8, 1995: VOG, Document created.
Jul 27, 2000: VOG, Changed local 'getipval' to
library 'interpol'.