Ubuntu Manpage: Areas_params - This document briefly describes all Areas parameters.

Provided by: libncarg-dev_6.6.2.dfsg.1-10build2_amd64

NAME

       Areas_params - This document briefly describes all Areas parameters.

DESCRIPTION

Areas currently supports nine parameters. These parameters are useful mostly for debugging Areas
problems. The current values may be retrieved using one of the routines ARGETI or ARGETR. Parameter
values may be reset using the routine ARSETI or ARSETR; the parameter 'DI' is for retrieval only and may
not be given a new value by the user.

The Areas parameter descriptions appear below in alphabetical order. Each description begins with a line
giving the parameter name and the intrinsic FORTRAN type of the parameter.

'AL' - Real
Arrowhead Length. AL specifies the length of each arrowhead used on a debug plot produced by
ARDBPA. The value is interpreted as a fraction of the width of the plotter frame. Using a value
which is less than or equal to zero causes arrowheads to be omitted. The default value is .008.

'AT' - Integer
Arithmetic Type flag. AT allows the user to specify the type of arithmetic Areas is to use or to
find out what type it decided to use. A call to set the value of AT should precede any other call
to an Areas routine (except, possibly, one to set the value of LC) and it should only be done
once. A call to get the value of AT will either return the value you set or a value picked by
Areas.

< 1 Areas decides what sort of arithmetic to use.

1 Real arithmetic is to be used.

2 Double-precision arithmetic is to be used.

3 Multiple-precision arithmetic is to be used and Areas is to choose the base value.

> 3 Multiple-precision arithmetic is to be used and AT specifies the base value. (For example,
the value 100 specifies the use of base-100 multiple-precision integer arithmetic.)

Default: 0

Note: You should use a nonzero value of AT only on the recommendation of an NCAR consultant.

'AW' - Real
Arrowhead Width. AL specifies the half-width of each arrowhead used on a debug plot produced by
ARDBPA. The value is interpreted as a fraction of the width of the plotter frame. Using a value
which is less than or equal to zero causes arrowheads to be omitted. The default value is .002.

'DB' - Integer
DeBug-plots flag. DB allows the user to study the area map.

0 Debugging turned off. This is the default.

> 0 Debugging is on. At selected break points, ARPRAM produces plots showing all edge segments in
the area map that belong to the edge group with group identifier DB.

'DC' - Integer
Debug Colors index. ARDBPA uses color indices DC+1 through DC+5 for debug-plot colors.

By default, DC=100, so ARDBPA defines and uses color indices 101 through 105.

'DI' - Integer
Direction Indicator flag. The value of DI is for retrieval only and cannot be set by the user. A
value returned for DI is meaningful only when the call to ARGETI that retrieves it originates from
the user-written routine (dummy argument "APR") that is called by ARSCAM. It then gives you
information about the area whose polygonal boundary is defined by the values of APR's arguments.
The two possible values of DI are:

1 Edge of the area is given in counterclockwise order (with the interior to the left).

2 Edge of the area is given in clockwise order (with the interior to the right).

'ID' - Real
Identifier Distance. ID specifies the distance from an arrow to a left or right area identifier
on a debug plot produced by ARDBPA. The value is interpreted as a fraction of the width of the
plotter frame. Using a value which is less than or equal to zero causes area identifiers to be
omitted. The default value is .004.

'IS' - Real
Identifier Size. IS specifies the size of the characters used to write an area identifier on a
debug plot produced by ARDBPA. The value is interpreted as a fraction of the width of the plotter
frame. Using a value which is less than or equal to zero causes area identifiers to be omitted.
The default value is .001.

'LC' - Integer
Largest Coordinate. LC lets you specify the largest coordinate allowed in an area map. X and Y
coordinates in an area map are represented by integers in the range from 0 to LC, inclusive; the
default value of LC is 1000000.

The minimum value allowed for LC is 1000; attempting to set LC<1000 gives it the value 1000. The
value of LC must not be greater than the largest integer on the machine on which Areas is running;
its value must also be exactly representable as a real number on that machine.

A call to set the value of LC should precede any other call to an Areas routine and should only be
done once.

'RC' - Integer
Reconciling Conflicts in area-identifier information.

This is an array of 16 values, indexed by group identifier. To set all values in the array to the
same value "n", use "CALL ARSETI('RC',n)"; to set just the first value in the array, use "CALL
ARSETI('RC(1)',n)"; to set just the second value, use "CALL ARSETI('RC(2)',n)"; and so on. You
can call ARGETI to get the value of RC(1) or RC(2) or RC(3), etc.; if you ask for the value of
just RC, you will get the value of RC(1).

RC(1) is associated with edge group 1, RC(2) with edge group 2, and so on. An edge group with a
group identifier greater than 16 is associated with RC(16).

When the set of possible area identifiers for a given area in a given group is contradictory, some
algorithm must be used to choose an identifier for the area. The value of that element of RC that
is associated with the group determines what algorithm will be used, as follows:

0 The default scheme: If any of the possible area identifiers is negative, use -1 as the
identifier for the area. Otherwise, if none of the possible values is non-zero, use a zero
identifier. Otherwise, from among the non-zero possibilities, use the one most recently seen
by AREAS.

1 The set of possible identifiers is examined: Zeroes are ignored, negatives are treated as
-1's, and the value that occurs most frequently in the resulting set is used as the
identifier for the area.

2 Using RC = 2 is just like using RC = 1 except that zeroes are not ignored: the area
identifier used is simply the one that occurs most frequently in the set of possibilities
(all negatives being treated as -1's).

-1 Using RC = -1 is just like using RC = 1 except that, if there are any negatives in the set of
possible identifiers, a -1 is used.

-2 Using RC = -2 is just like using RC = 2 except that, if there are any negatives in the set of
possible identifiers, a -1 is used.

COPYRIGHT

       Copyright (C) 1987-2009
       University Corporation for Atmospheric Research
       The use of this Software is governed by a License Agreement.

UNIX                                               April 1995                               Areas_params(3NCARG)

NAME

DESCRIPTION

SEE ALSO

COPYRIGHT