SAGA-GIS Tool Library Documentation (v6.2.0)

Tool Thin Plate Spline (TIN)

Creates a 'Thin Plate Spline' function for each triangle of a TIN and uses it for subsequent gridding. The TIN is internally created from the scattered data points input. The 'Neighbourhood' option determines the number of points used for the spline generation. 'Immediate neighbourhood' includes the points of the triangle as well as the immediate neighbour points. 'Level 1' adds the neighbours of the immediate neighbourhood and 'level 2' adds the neighbours of 'level 1' neighbours too. A higher neighbourhood degree reduces sharp breaks but also increases the computation time.

References:
- Donato G., Belongie S. (2002): 'Approximation Methods for Thin Plate Spline Mappings and Principal Warps', In Heyden, A., Sparr, G., Nielsen, M., Johansen, P. (Eds.): 'Computer Vision - ECCV 2002: 7th European Conference on Computer Vision, Copenhagen, Denmark, May 28-31, 2002', Proceedings, Part III, Lecture Notes in Computer Science. Springer-Verlag Heidelberg; pp.21-31.

- Elonen, J. (2005): 'Thin Plate Spline editor - an example program in C++', http://elonen.iki.fi/code/tpsdemo/index.html.

Parameters

 NameTypeIdentifierDescriptionConstraints
InputPointsShapes (input)SHAPES--
Target System (*)Grid (optional input)TARGET_TEMPLATEuse this grid's system for output grids-
OutputTarget GridGrid (output)TARGET_OUT_GRID--
OptionsAttributeTable fieldFIELD--
Target Grid SystemChoiceTARGET_DEFINITION-Available Choices:
[0] user defined
[1] grid or grid system
Default: 0
CellsizeFloating pointTARGET_USER_SIZE-Minimum: 0.000000
Default: 1.000000
LeftFloating pointTARGET_USER_XMIN-Default: 0.000000
RightFloating pointTARGET_USER_XMAX-Default: 100.000000
BottomFloating pointTARGET_USER_YMIN-Default: 0.000000
TopFloating pointTARGET_USER_YMAX-Default: 100.000000
FitChoiceTARGET_USER_FITS-Available Choices:
[0] nodes
[1] cells
Default: 0
Grid SystemGrid systemTARGET_SYSTEM--
RegularisationFloating pointREGULARISATION-Minimum: 0.000000
Default: 0.000100
NeighbourhoodChoiceLEVEL-Available Choices:
[0] immediate
[1] level 1
[2] level 2
Default: 1
Add FrameBooleanFRAME-Default: 1
(*) optional

Command-line

Usage: saga_cmd grid_spline 2 [-SHAPES <str>] [-FIELD <str>] [-TARGET_DEFINITION <str>] [-TARGET_USER_SIZE <double>] [-TARGET_USER_XMIN <double>] [-TARGET_USER_XMAX <double>] [-TARGET_USER_YMIN <double>] [-TARGET_USER_YMAX <double>] [-TARGET_USER_FITS <str>] [-TARGET_TEMPLATE <str>] [-TARGET_OUT_GRID <str>] [-REGULARISATION <double>] [-LEVEL <str>] [-FRAME <str>]
  -SHAPES:<str>             	Points
	Shapes (input)
  -FIELD:<str>              	Attribute
	Table field
  -TARGET_DEFINITION:<str>  	Target Grid System
	Choice
	Available Choices:
	[0] user defined
	[1] grid or grid system
	Default: 0
  -TARGET_USER_SIZE:<double>	Cellsize
	Floating point
	Minimum: 0.000000
	Default: 1.000000
  -TARGET_USER_XMIN:<double>	Left
	Floating point
	Default: 0.000000
  -TARGET_USER_XMAX:<double>	Right
	Floating point
	Default: 100.000000
  -TARGET_USER_YMIN:<double>	Bottom
	Floating point
	Default: 0.000000
  -TARGET_USER_YMAX:<double>	Top
	Floating point
	Default: 100.000000
  -TARGET_USER_FITS:<str>   	Fit
	Choice
	Available Choices:
	[0] nodes
	[1] cells
	Default: 0
  -TARGET_TEMPLATE:<str>    	Target System
	Grid (optional input)
  -TARGET_OUT_GRID:<str>    	Target Grid
	Grid (output)
  -REGULARISATION:<double>  	Regularisation
	Floating point
	Minimum: 0.000000
	Default: 0.000100
  -LEVEL:<str>              	Neighbourhood
	Choice
	Available Choices:
	[0] immediate
	[1] level 1
	[2] level 2
	Default: 1
  -FRAME:<str>              	Add Frame
	Boolean
	Default: 1