User's Guide

EDITGRID

Edit the contents of a grid file.

Function:

Edits the polynomial and projection information in a geometric mapping grid file and/or creates a new geometric mapping grid file with this information. EDITGRID provides two methods for modifying a grid file, a screen mode and tutor mode. Since the actual mapping grid is not created or modified, the output grid file is used by GRIDGEN to generate a geometric mapping grid for use with RESAMPLE.

Parameters:

Subcommand -SCREEN:
Screen mode. In this mode the changeable values of the geometric mapping grid file are displayed on the screen and the user may interactively edit the fields.

NOTE: This subcommand cannot be used for BATCH processing.

INGRID(--)
Input grid file. Input geometric mapping grid file to be edited. To create a new grid file, INGRID must be set to NULL (--).

OUTGRID
Output grid file. The output geometric mapping grid file containing transformation coefficients and projection information.
Subcommand -TUTOR:
Tutor mode. In this mode the user can enter values for any of the changeable fields of the geometric mapping grid file.

NOTE: Use this subcommand for BATCH processing.

INGRID(--)
Input grid file. Input geometric mapping grid file to be edited. To create a new grid file, INGRID must be set to NULL (--).

OUTGRID
Output grid file. The output geometric mapping grid file containing transformation coefficients and projection information.

NCOEF(--)
Number of coefficients. The number of coefficients in each of the polynomials. The valid entries are 3,6,10,15 for a first, second, third, or fourth degree polynomial. This parameter is required when the grid file does not exist.

LINECOEF(-- )
Line coefficients. Coefficients describing the transformation to be applied to the line coordinates (Y-direction). This parameter is required when the grid file does not exist. Up to a fourth order polynomial may be entered. Coefficients should be entered in the following manner:


 LINECOEF(1):   Constant     
 LINECOEF(2):   X           
 LINECOEF(3):   Y          
 LINECOEF(4):   X**2      
 LINECOEF(5):   XY       
 LINECOEF(6):   Y**2    
 LINECOEF(7):   X**3   
 LINECOEF(8):   (X**2)Y      
 LINECOEF(9):   X(Y**2)     
 LINECOEF(10):  Y**3       
 LINECOEF(11):  X**4      
 LINECOEF(12):  (X**3)Y  
 LINECOEF(13):  (X**2)(Y**2) 
 LINECOEF(14):  X(Y**3)     
 LINECOEF(15):  Y**4       

SAMPCOEF(-- )
Sample coefficients. Coefficients describing the transformation to be applied to the sample coordinates (X-direction). This parameter is required when the grid file does not exist. Up to a fourth order polynomial may be entered. Coefficients should be entered in the following manner:


 SAMPCOEF(1):   Constant     
 SAMPCOEF(2):   X           
 SAMPCOEF(3):   Y          
 SAMPCOEF(4):   X**2      
 SAMPCOEF(5):   XY       
 SAMPCOEF(6):   Y**2    
 SAMPCOEF(7):   X**3   
 SAMPCOEF(8):   (X**2)Y      
 SAMPCOEF(9):   X(Y**2)     
 SAMPCOEF(10):  Y**3       
 SAMPCOEF(11):  X**4      
 SAMPCOEF(12):  (X**3)Y  
 SAMPCOEF(13):  (X**2)(Y**2) 
 SAMPCOEF(14):  X(Y**3)     
 SAMPCOEF(15):  Y**4       

MODEL(--)
Model method. Type of model used to generate the geometric mapping grid. Standard values are "POLYNOMIAL," "SPACECRAFT," and "FINITE ELEMENT." Other values are allowed, if need be. This parameter is required when the grid file does not exist.

PPVAL(--)
Projection parameters validity. The validity of the projection parameter values.


  = IN:   Invalid.  The value is known to be invalid.
  = VAL:  Valid.  The value is known to be valid.

PROJTYPE(--)
Projection type. The types used by the LAS Projection Transformation Package to indicate map projection systems. Refer to the Geometric Manipulation Package Overview Document for further details. Valid projection system types are:


  = GEO(0):      Geographic   
  = UTM(1):	 Universal Transverse Mercator
  = SPCS(2):	 State Plane Coordinate System
  = ALBERS(3):	 Albers Conical Equal Area
  = LAMCC(4):	 Lambert Conformal Conic
  = MERCAT(5):   Mercator
  = PS(6):	 Polar Stereographic
  = POLYC(7):	 Polyconic
  = EQUIDC(8):	 Equidistant Conic
  = TM(9):	 Transverse Mercator
  = STEREO(10):	 Stereographic
  = LAMAZ(11):   Lambert Azimuthal Equal-Area
  = AZMEQD(12):	 Azimuthal Equidistant
  = GNOMON(13):	 Gnomonic
  = ORTHO(14):	 Orthographic
  = GVNSP(15):	 General Vertical Near-Side Perspective
  = SNSOID(16):	 Sinusoidal
  = EQRECT(17):	 Equi-rectangular
  = MILLER(18):	 Miller Cylindrical
  = VGRINT(19):	 Van der Grinten
  = HOM(20):	 Hotine Oblique Mercator
  = ROBIN(21):	 Robinson
  = SOM(22):	 Space Oblique Mercator
  = ALASKA(23):	 Alaska Conformal
  = GOOD(24):	 Interrupted Goode Homolosine
  = MOLL(25):	 Mollweide
  = IMOLL(26):	 Interrupted Mollweide
  = HAMMER(27):  Hammer
  = WAGIV(28):	 Wagner IV
  = WAGVII(29):	 Wagner VII
  = OBEQA(30):	 Oblated Equal Area
  = USERDEF:     User defined

ZONENUM(--)
Zone number. The zone to use for UTM and State Plane projection systems. Refer to the Geometric Manipulation Package Overview Document (GEOMPOD) for further details.

DCODE(--)
Datum code. The datum can be used for setting the semimajor axis and eccentricity squared for a particular projection. Refer to the LAS Projection Transformation Package for further details. The supported datum codes are:


  0 = Clarke 1866 
  1 = Clarke 1880
  2 = Bessel
  3 = International 1967
  4 = International 1909
  5 = WGS 72
  6 = Everest
  7 = WGS 66
  8 = GRS 1980
  9 = Airy
 10 = Modified Everest
 11 = Modified Airy
 12 = Walbeck
 13 = Southeast Asia
 14 = Australian National
 15 = Krassovsky
 16 = Hough
 17 = Mercury 1960
 18 = Modified Mercury 1968
 19 = Sphere of Radius 6370997 meters

PROJPARM(--)
Projection parameters. These parameters are required to define each map projection. Refer to the LAS Projection Transformation Package for further details.

UPLEFT(--)
Upper-left corner coordinates. The location of the upper-left corner. The coordinates are entered in latitude/longitude or northing/easting order.

LOLEFT(--)
Lower-left corner coordinates. The location of the lower-left corner. The coordinates are entered in latitude/longitude or northing/easting order.

UPRIGHT(--)
Upper-right corner coordinates. The location of the upper-right corner. The coordinates are entered in latitude/longitude or northing/easting order.

LORIGHT(--)
Lower-right corner coordinates. The location of the lower-right corner. The coordinates are entered in latitude/longitude or northing/easting order.

PDLINE(--)
Projection distance in line direction. The distance on the ground (in the line direction) that one sample represents in projection units.

PDSAMP(--)
Projection distance in sample direction. The distance on the ground (in the sample direction) that one sample represents in projection units.

PUNITS(--)
Projection measurement units. The measurement system used for the projection dimensions. The current standard projection units include the following (all others are user-defined):


  radians
  degrees
  seconds
  dms
  feet
  meters

Examples:

  1. LAS> editgrid-screen ingrid=test.grid outgrid=new.grid

    EDITGRID will read the contents of TEST.GRID. The values of each of the fields will be printed to the terminal screen. The user then interactively edits any of the fields on the screen. These changes will only be written to NEW.GRID when the WRITE command is invoked.

  2. LAS> editgrid-tutor ingrid=test.grid outgrid=new.grid ncoef=3 linecoef=(0,.707,.707) sampcoef=(0,.707,-.707)

    EDITGRID will read the contents of TEST.GRID and change the contents of the fields NCOEF, LINECOEF and SAMPCOEF. The parameters (fields) that were defaulted by the user will not be changed. All the values of the fields will be written to NEW.GRID.

  3. LAS> editgrid-screen ingrid=-- outgrid=temp.grid

    EDITGRID will print the values of a blank grid file to the terminal screen. The user then interactively edits any of the fields on the screen. These changes will only be written to TEMP.GRID when the WRITE command is invoked and the model method, number of coefficients, and the transformation coefficients have been entered.

Description/Algorithm:

EDITGRID edits the polynomial and projection information in a geometric mapping grid file and/or creates a new geometric mapping grid file with this information. Two methods are used for modifying a grid file, a screen mode and tutor mode. Since the actual mapping grid is not created or modified, the output geometric mapping grid information is used by GRIDGEN for grid generation. EDITGRID-SCREEN reads the contents of the input grid file and prints each of the fields to the terminal screen. The user can then interactively edit any of the fields on the screen. These changes are only written to OUTGRID when the WRITE command is invoked. To create a new grid file, INGRID must be set to NULL (--) and the number of coefficients, transformation coefficients, and model method must be set.

Valid commands of the -SCREEN subcommand:
   (H)elp  -- retrieve help for any of the grid fields
   (P)age  -- go to the next screen of information
   (Q)uit  -- end the session without updating the grid file
   (W)rite -- write the changes to the grid file and end the session

EDITGRID-TUTOR reads the contents of the file and then changes the contents of the fields for which the user enters values. The parameters (fields) that were defaulted by the user are not changed. All the values of the fields are written to the grid file specified by the parameter OUTGRID. To create a new grid file, INGRID must be set to NULL (--) and NCOEF, LINECOEF, SAMPECOEF, and MODEL are then required parameters. All other parameters that were defaulted by the user have a value of zero or a blank.

Nonfatal Error Messages:

  1. [editgrid-code] Invalid <XXXX> command code

    An invalid <XXXX> command code was entered. Retype the command with the correct code. The upper-case letters or a combination of the upper-case letters should be used as the edit command code.

  2. [editgrid-datum] Invalid datum code

    An invalid datum code was specified. Re-enter a valid datum code. Valid datum codes range from 0 through 19.

  3. [editgrid-input] Input is larger than buffer size

    The string that was input is larger than the size of the input buffer. Since the input string is larger than the buffer size, the string is probably invalid. Re-enter a shorter string.

  4. [editgrid-length] String length is too long

    The length of the input string is too long for the width of the field within the grid. Shorten the input string.

  5. [editgrid-syntax] Invalid syntax of an edit command

    The edit command was not entered in correct syntax. Retype the command with the correct syntax as follows.

    edit command code = new value

  6. [editgrid-value] Unacceptable valid value

    An unacceptable value was entered for the VALID field. Retype the command with a correct value. The correct values are:

    IN: Invalid VAL: Valid

  7. [editgrid-zone] Invalid zone code

    An invalid zone code was specified. Re-enter a valid zone code. Refer to the Geometric Manipulation Package Overview Document (GEOMPOD) for valid zone codes.

  8. [editgrid-ncoef] Invalid number of coefficients.

    An invalid number of coefficients was specified. The valid entries are 3,6,10,15 for a first, second, third, or fourth degree polynomial.

Fatal Error Messages:

  1. [editgrid-create] <XXXX> is required when a grid is being created

    <XXXX> is a required parameter in order to create a valid new grid file. Enter a valid value into the <XXXX> parameter.

  2. [editgrid-device] Device is not a terminal

    The device from which this module was initiated is not a terminal. To use this module with the subcommand -SCREEN, this module must be initiated on a terminal and not in batch.

  3. [editgrid-display] Terminal has too few lines of display area

    The terminal from which this module was initiated does not have enough lines in which to display the contents of the grid correctly. Initiate this module using the subcommand -TUTOR or initiate this module from a terminal that has at least 24 lines of display.

  4. [editgrid-fatal] Fatal error encountered

    A fatal error was encountered during processing. The output grid file was not created, and processing is terminated. The message that is displayed immediately preceding this error message is the specific error that was encountered.

  5. [editgrid-terminal] Terminal is not supported by TAE I/O

    The terminal from which this module was initiated is not supported by TAE terminal I/O. Initiate this module on a terminal that is supported by TAE terminal I/O. Consult the TAE Users' Manual for a list of valid terminal types.

  6. [editgrid-write] Error writing to the grid file

    An error occurred while writing the grid file. Verify that disk space is available.

  7. [editgrid-projcode] Invalid projection code

    An invalid projection code was entered. Retype the command with a valid projection code. See PROJTYPE for valid projection codes.

  8. [editgrid-poly] Invalid polynomial entry

    The number of transformation coefficients entered for the polynomial is greater than the number of coefficients allowed for this degree of polynomial. Re-enter the transformation coefficients or change NCOEF to change the degree of the polynomial.

  9. [editgrid-alloc] Error allocating memory for geometric mapping grid

    An error occurred allocating memory for the output geometric mapping grid file. Rerun the function, and if the error reoccurs, contact the system manager.

User Notes:

  1. Related modules include DSPGRID and GRIDGEN.

  2. For more information on geometric mapping grids, refer to the Geometric Manipulation Package Overview Document, GEOMPOD.

  3. Some of the fatal error messages are informational error messages for the SCREEN mode. In the SCREEN mode, the user is allowed to correct the error before creating the grid file.