SUBROUTINE WCI_CNA2P( APOS, PIXID, PPOS, STATUS ) *+ * Name: * WCI_CNA2P * Purpose: * Convert position in axis units to pixels * Language: * Starlink Fortran * Invocation: * CALL WCI_CNA2P( APOS, PIXID, PPOS, STATUS ) * Description: * Converts a position APOS in axis units into a continuous pixel * position using the pixellation data in PIXID. * Arguments: * APOS[2] = REAL (given) * Position in axis units * PIXID = INTEGER (given) * ADI identifier of pixellation object * PPOS[2] = REAL (returned) * Position in fractional pixels * STATUS = INTEGER (given and returned) * The global status. * Examples: * {routine_example_text} * {routine_example_description} * Pitfalls: * {pitfall_description}... * Notes: * {routine_notes}... * Prior Requirements: * {routine_prior_requirements}... * Side Effects: * {routine_side_effects}... * Algorithm: * {algorithm_description}... * Accuracy: * {routine_accuracy} * Timing: * {routine_timing} * External Routines Used: * {name_of_facility_or_package}: * {routine_used}... * Implementation Deficiencies: * {routine_deficiencies}... * References: * WCI Subroutine Guide : http://www.sr.bham.ac.uk/asterix-docs/Programmer/Guides/wci.html * Keywords: * package:wci, usage:private * Copyright: * Copyright (C) University of Birmingham, 1995 * Authors: * DJA: David J. Allan (Jet-X, University of Birmingham) * {enter_new_authors_here} * History: * 6 Jan 1995 (DJA): * Original version. * {enter_changes_here} * Bugs: * {note_any_bugs_here} *- * Type Definitions: IMPLICIT NONE ! No implicit typing * Global Constants: INCLUDE 'SAE_PAR' ! Standard SAE constants INCLUDE 'AST_PKG' * Arguments Given: REAL APOS(2) INTEGER PIXID * Arguments Returned: REAL PPOS(2) * Status: INTEGER STATUS ! Global status * External References: EXTERNAL AST_QPKGI LOGICAL AST_QPKGI * Local Variables: REAL ABASE(2) ! Axis val at pix 1 REAL ASCALE(2) ! Bin width INTEGER DUM ! Array size *. * Check inherited global status. IF ( STATUS .NE. SAI__OK ) RETURN * Check initialised IF ( .NOT. AST_QPKGI( WCI__PKG ) ) CALL WCI1_INIT( STATUS ) * Get axis scalings CALL ADI_CGET1R( PIXID, 'BASE', 2, ABASE, DUM, STATUS ) CALL ADI_CGET1R( PIXID, 'SCALE', 2, ASCALE, DUM, STATUS ) * Calculate pixel values PPOS(1) = (APOS(1) - ABASE(1))/ASCALE(1) + 1.0 PPOS(2) = (APOS(2) - ABASE(2))/ASCALE(2) + 1.0 * Report any errors IF ( STATUS .NE. SAI__OK ) CALL AST_REXIT( 'WCI_CNA2P', STATUS ) END