SAGA-GIS Tool Library Documentation (v6.1.0)

Tool Create Grid System

This tool creates a new user specified Grid System for use with other tools.

First of all, please consider the following issues before using the tool:
(a) all calculations of the tool refer to the lower left corner of the grid system, i.e. the xMin and yMin values. This coordinate is fixed unless you specify an offset.
(b) the tool follows the philosophy of SAGA in that the values describing the extent refer to the cell centers. If you like to match the extent with the border of a grid, use an offset.

The tool provides four possibilities to set/determine the extent of the grid system:
(1) by specifying the coordinate of the lower left cell (xMin, yMin) and the number of cells in W-E (NX) and S-N (NY) direction
(2) by specifying the coordinates the of lower left (xMin, yMin) and the upper right (xMax, yMax) cell
(3) by the extent of the shape(s) provided in the Data Objects section
(4) by the extent of the grid(s) provided in the Data Objects section

After selecting the appropriate method to determine the extent, the next step is to specify the Cellsize of the new grid system.
For all methods supplied to determine the extent but number (1), three possibilities are provided to adjust Cellsize and grid system extent (please remember, the lower left corner is fixed!):
(I) adjust the extent to match the Cellsize
(II) adjust the Cellsize to match the extent in E-W direction
(III) adjust the Cellsize to match the extent in S-N direction

Finally it is possible to apply an offset to the lower left corner of the grid system. In this case check the Use Offset option and specify the offset in W-E and S-N direction. Positive values result in a shift in E/N, negative in W/S direction.
In order to create the grid system the tool needs to create a dummy grid.

Parameters

 NameTypeIdentifierDescriptionConstraints
InputShapes LayersShapes list (input)SHAPESLIST--
GridsGrid list (input)GRIDLIST--
OutputDummy Grid (*)Data Object (optional output)GRID--
OptionsInitialization ValueFloating pointINITValue which is assigned to the dummy grid.Default: 0.000000
CellsizeFloating pointCELLSIZE-Minimum: 0.000000
Default: 10.000000
Extent DefinitionChoiceM_EXTENT-Available Choices:
[0] lower left coordinate and number of rows and columns
[1] lower left and upper right coordinates
[2] one or more shapes layers
[3] one or more grids
Default: 0
AdjustChoiceADJUST-Available Choices:
[0] extent to cell size
[1] cell size to left-right extent
[2] cell size to bottom-top extent
Default: 0
LeftFloating pointXMIN-Default: 0.000000
RightFloating pointXMAX-Default: 100.000000
ColumnsIntegerNX-Minimum: 1
Default: 10
BottomFloating pointYMIN-Default: 0.000000
TopFloating pointYMAX-Default: 100.000000
RowsIntegerNY-Minimum: 1
Default: 10
Use OffsetBooleanUSEOFF-Default: 0
X OffsetFloating pointXOFFSETPositive values result in a shift in E direction.Default: 0.000000
Y OffsetFloating pointYOFFSETPositive values result in a shift in N direction.Default: 0.000000
(*) optional

Command-line

Usage: saga_cmd grid_tools 23 [-GRID <str>] [-INIT <double>] [-CELLSIZE <double>] [-M_EXTENT <str>] [-ADJUST <str>] [-XMIN <double>] [-XMAX <double>] [-NX <num>] [-YMIN <double>] [-YMAX <double>] [-NY <num>] [-SHAPESLIST <str>] [-GRIDLIST <str>] [-USEOFF <str>] [-XOFFSET <double>] [-YOFFSET <double>]
  -GRID:<str>       	Dummy Grid
	Data Object (optional output)
  -INIT:<double>    	Initialization Value
	Floating point
	Default: 0.000000
  -CELLSIZE:<double>	Cellsize
	Floating point
	Minimum: 0.000000
	Default: 10.000000
  -M_EXTENT:<str>   	Extent Definition
	Choice
	Available Choices:
	[0] lower left coordinate and number of rows and columns
	[1] lower left and upper right coordinates
	[2] one or more shapes layers
	[3] one or more grids
	Default: 0
  -ADJUST:<str>     	Adjust
	Choice
	Available Choices:
	[0] extent to cell size
	[1] cell size to left-right extent
	[2] cell size to bottom-top extent
	Default: 0
  -XMIN:<double>    	Left
	Floating point
	Default: 0.000000
  -XMAX:<double>    	Right
	Floating point
	Default: 100.000000
  -NX:<num>         	Columns
	Integer
	Minimum: 1
	Default: 10
  -YMIN:<double>    	Bottom
	Floating point
	Default: 0.000000
  -YMAX:<double>    	Top
	Floating point
	Default: 100.000000
  -NY:<num>         	Rows
	Integer
	Minimum: 1
	Default: 10
  -SHAPESLIST:<str> 	Shapes Layers
	Shapes list (input)
  -GRIDLIST:<str>   	Grids
	Grid list (input)
  -USEOFF:<str>     	Use Offset
	Boolean
	Default: 0
  -XOFFSET:<double> 	X Offset
	Floating point
	Default: 0.000000
  -YOFFSET:<double> 	Y Offset
	Floating point
	Default: 0.000000