Interpolation - Revision history

Neteler: /* Resampling of raster maps to coarser resolution */

2023-05-16T20:58:14Z

Resampling of raster maps to coarser resolution

← Older revision		Revision as of 20:58, 16 May 2023
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	==== Resampling of raster maps to coarser resolution ====		==== Resampling of raster maps to coarser resolution ====
	* ~~For~~ {{cmd\|r.resamp.stats}} resamples raster map layers to a coarser grid using aggregation. Used without -w, the value of each region cell is the chosen aggregate of the values from all of the raster cells whose centres fall within the bounds of the region cell. With -w, the samples are weighted according to the proportion of the raster cell which falls within the bounds of the region cell, so the result is normally unaffected by rounding error (a miniscule difference in the position of the boundary results in the addition or subtraction of a sample weighted by a miniscule factor; also, The min and max aggregates can't use weights, so -w has no effect for those).		* {{cmd\|r.resamp.stats}} resamples raster map layers to a coarser grid using aggregation. Used without -w, the value of each region cell is the chosen aggregate of the values from all of the raster cells whose centres fall within the bounds of the region cell. With -w, the samples are weighted according to the proportion of the raster cell which falls within the bounds of the region cell, so the result is normally unaffected by rounding error (a miniscule difference in the position of the boundary results in the addition or subtraction of a sample weighted by a miniscule factor; also, The min and max aggregates can't use weights, so -w has no effect for those).

	=== Reinterpolation of "sparse" (scattered points or lines) maps ===		=== Reinterpolation of "sparse" (scattered points or lines) maps ===

Neteler: r.fill.gaps addon -> r.fill.stats in core

2020-10-12T14:57:06Z

r.fill.gaps addon -> r.fill.stats in core

← Older revision		Revision as of 14:57, 12 October 2020
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	[[Image:Inlets_03_SurfSal_icw_big.png\|200px\|right\|thumb\|v.surf.icw interpolating around barriers]]		[[Image:Inlets_03_SurfSal_icw_big.png\|200px\|right\|thumb\|v.surf.icw interpolating around barriers]]

	* Inverse distance weighted average ({{wikipedia\|Inverse_distance_weighting\|IDW}}) interpolation ({{cmd\|v.surf.idw}}, {{cmd\|r.surf.idw}}, and {{~~AddonCmd~~\|r.fill.~~gaps\|version=7~~}} ~~Addon~~)		* Inverse distance weighted average ({{wikipedia\|Inverse_distance_weighting\|IDW}}) interpolation ({{cmd\|v.surf.idw}}, {{cmd\|r.surf.idw}}, and {{cmd\|r.fill.stats}})
	* Interpolating from contour lines ({{cmd\|r.surf.contour}}), see [[Contour lines to DEM]]		* Interpolating from contour lines ({{cmd\|r.surf.contour}}), see [[Contour lines to DEM]]
	* Interpolating using {{wikipedia\|Natural_neighbor}} method ({{AddonCmd\|r.surf.nnbathy}})		* Interpolating using {{wikipedia\|Natural_neighbor}} method ({{AddonCmd\|r.surf.nnbathy}})
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	Sometimes no-data areas in raster maps (continuous surfaces) needs to be filled using interpolation:		Sometimes no-data areas in raster maps (continuous surfaces) needs to be filled using interpolation:
	* see {{cmd\|r.fillnulls}}		* see {{cmd\|r.fillnulls}}
	* {{~~AddonCmd~~\|r.fill.~~gaps\|version=7~~}}		* see {{cmd\|r.fill.stats}} (IDW based, very fast)

	Optionally extra raster sample points can be generated from an auxiliary raster maps using {{cmd\|r.random}}, merged into the target raster maps with {{cmd\|r.patch}} and then filled using interpolation with {{cmd\|r.fillnulls}}.		Optionally extra raster sample points can be generated from an auxiliary raster maps using {{cmd\|r.random}}, merged into the target raster maps with {{cmd\|r.patch}} and then filled using interpolation with {{cmd\|r.fillnulls}}.

Neteler: /* Filling of holes */ +r.fill.gaps

2020-09-22T17:35:24Z

Filling of holes: +r.fill.gaps

← Older revision		Revision as of 17:35, 22 September 2020
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	Sometimes no-data areas in raster maps (continuous surfaces) needs to be filled using interpolation:		Sometimes no-data areas in raster maps (continuous surfaces) needs to be filled using interpolation:
	* see {{cmd\|r.fillnulls}}		* see {{cmd\|r.fillnulls}}
			* {{AddonCmd\|r.fill.gaps\|version=7}}

	Optionally extra raster sample points can be generated from an auxiliary raster maps using {{cmd\|r.random}}, merged into the target raster maps with {{cmd\|r.patch}} and then filled using interpolation with {{cmd\|r.fillnulls}}.		Optionally extra raster sample points can be generated from an auxiliary raster maps using {{cmd\|r.random}}, merged into the target raster maps with {{cmd\|r.patch}} and then filled using interpolation with {{cmd\|r.fillnulls}}.

Neteler: +r.fill.gaps

2020-09-19T21:18:01Z

+r.fill.gaps

← Older revision		Revision as of 21:18, 19 September 2020
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	[[Image:Inlets_03_SurfSal_icw_big.png\|200px\|right\|thumb\|v.surf.icw interpolating around barriers]]		[[Image:Inlets_03_SurfSal_icw_big.png\|200px\|right\|thumb\|v.surf.icw interpolating around barriers]]

	* Inverse distance weighted average ({{wikipedia\|Inverse_distance_weighting\|IDW}}) interpolation ({{cmd\|v.surf.idw}}, {{cmd\|r.surf.idw}}, and {{AddonCmd\|r.~~surf~~.~~idw2~~\|version=7}} Addon)		* Inverse distance weighted average ({{wikipedia\|Inverse_distance_weighting\|IDW}}) interpolation ({{cmd\|v.surf.idw}}, {{cmd\|r.surf.idw}}, and {{AddonCmd\|r.fill.gaps\|version=7}} Addon)
	* Interpolating from contour lines ({{cmd\|r.surf.contour}}), see [[Contour lines to DEM]]		* Interpolating from contour lines ({{cmd\|r.surf.contour}}), see [[Contour lines to DEM]]
	* Interpolating using {{wikipedia\|Natural_neighbor}} method ({{AddonCmd\|r.surf.nnbathy}})		* Interpolating using {{wikipedia\|Natural_neighbor}} method ({{AddonCmd\|r.surf.nnbathy}})

Neteler: remove hardcoded version specific urls, use latest version

2018-12-04T10:52:34Z

remove hardcoded version specific urls, use latest version

← Older revision		Revision as of 10:52, 4 December 2018
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	== Resampling methods and interpolation in GRASS ==		== Resampling methods and interpolation in GRASS GIS ==

	=== Reinterpolation of "filled" raster maps (continuous data) to a different resolution ===		=== Reinterpolation of "filled" raster maps (continuous data) to a different resolution ===
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	* {{cmd\|r.resamp.interp}} Resampling with nearest neighbor, bilinear, and bicubic method: method=nearest uses the same algorithm as {{cmd\|r.resample}}, but not the same code, so it may not produce identical results in cases which are decided by the rounding of floating-point numbers. For {{cmd\|r.resamp.interp}} method=bilinear and method=bicubic, the raster values are treated as samples at each raster cell's centre, defining a piecewise-continuous surface. The resulting raster values are obtained by sampling the surface at each region cell's centre. As the algorithm only interpolates, and doesn't extrapolate, a margin of 0.5 (for bilinear) or 1.5 (for bicubic) cells is lost from the extent of the original raster. Any samples taken within this margin will be null.		* {{cmd\|r.resamp.interp}} Resampling with nearest neighbor, bilinear, and bicubic method: method=nearest uses the same algorithm as {{cmd\|r.resample}}, but not the same code, so it may not produce identical results in cases which are decided by the rounding of floating-point numbers. For {{cmd\|r.resamp.interp}} method=bilinear and method=bicubic, the raster values are treated as samples at each raster cell's centre, defining a piecewise-continuous surface. The resulting raster values are obtained by sampling the surface at each region cell's centre. As the algorithm only interpolates, and doesn't extrapolate, a margin of 0.5 (for bilinear) or 1.5 (for bicubic) cells is lost from the extent of the original raster. Any samples taken within this margin will be null.
	* {{cmd\|r.resamp.rst}} Regularized Spline with Tension (RST) interpolation 2D: Behaves similarly, i.e. it computes a surface assuming that the values are samples at each raster cell's centre, and samples the surface at each region cell's centre.		* {{cmd\|r.resamp.rst}} Regularized Spline with Tension (RST) interpolation 2D: Behaves similarly, i.e. it computes a surface assuming that the values are samples at each raster cell's centre, and samples the surface at each region cell's centre.
			* {{cmd\|r.resamp.bspline}} resamples with bicubic or bilinear spline interpolation with Tykhonov regularization.
	~~Only GRASS 7:~~		* {{cmd\|r.resamp.filter}} resamples raster map layers using an analytic kernel. It offers box, bartlett, gauss, normal, hermite, sinc, lanczos1, lanczos2, lanczos3, hann, hamming, and blackman kernels.
	* {{cmd\|r.resamp.bspline~~\|version=70~~}} resamples with bicubic or bilinear spline interpolation with Tykhonov regularization.
	* {{cmd\|r.resamp.filter~~\|version=70~~}} resamples raster map layers using an analytic kernel. It offers box, bartlett, gauss, normal, hermite, sinc, lanczos1, lanczos2, lanczos3, hann, hamming, and blackman kernels.

	==== Resampling of raster maps to coarser resolution ====		==== Resampling of raster maps to coarser resolution ====
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	* Interpolating from vector points with {{wikipedia\|B-spline}}s ({{cmd\|v.surf.bspline}})		* Interpolating from vector points with {{wikipedia\|B-spline}}s ({{cmd\|v.surf.bspline}})
	* Interpolating from vector points with regularized splines with tension ({{cmd\|v.surf.rst}} and {{cmd\|v.vol.rst}}), see also [[RST Spline Surfaces]]		* Interpolating from vector points with regularized splines with tension ({{cmd\|v.surf.rst}} and {{cmd\|v.vol.rst}}), see also [[RST Spline Surfaces]]
	* Interpolating from vector points with {{wikipedia\|Kriging}} ({{cmd\|v.krige~~\|version=70~~}}~~, GRASS 7+~~)		* Interpolating from vector points with {{wikipedia\|Kriging}} ({{cmd\|v.krige}})
	* Interpolating from vector points around barriers or cost surfaces ({{AddonCmd\|v.surf.icw}})		* Interpolating from vector points around barriers or cost surfaces ({{AddonCmd\|v.surf.icw}})

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	* Statistical assessment: Use {{cmd\|r.mapcalc}} to calculate a differences map, then {{cmd\|r.univar}} to calculates univariate statistics of the differences		* Statistical assessment: Use {{cmd\|r.mapcalc}} to calculate a differences map, then {{cmd\|r.univar}} to calculates univariate statistics of the differences
	* Graphical comparison {{cmd\|g.gui.mapswipe~~\|version=70~~}} - Interactively compares two maps by swiping a visibility bar.		* Graphical comparison {{cmd\|g.gui.mapswipe}} - Interactively compares two maps by swiping a visibility bar.

	== See also ==		== See also ==

Neteler: +Filling of holes

2017-06-20T19:32:48Z

+Filling of holes

← Older revision		Revision as of 19:32, 20 June 2017
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	Vector points in XYZ format (CSV or ASCII file) can be rasterized (binning into raster cells) using univariate statistics:		Vector points in XYZ format (CSV or ASCII file) can be rasterized (binning into raster cells) using univariate statistics:
	* see ({{cmd\|r.in.xyz}})		* see ({{cmd\|r.in.xyz}})

			=== Filling of holes ===

			Sometimes no-data areas in raster maps (continuous surfaces) needs to be filled using interpolation:
			* see {{cmd\|r.fillnulls}}

			Optionally extra raster sample points can be generated from an auxiliary raster maps using {{cmd\|r.random}}, merged into the target raster maps with {{cmd\|r.patch}} and then filled using interpolation with {{cmd\|r.fillnulls}}.

	== Comparing original and interpolated data ==		== Comparing original and interpolated data ==

Neteler: /* Reinterpolation of "sparse" (scattered points or lines) maps */

2014-12-27T22:14:25Z

Reinterpolation of "sparse" (scattered points or lines) maps

← Older revision		Revision as of 22:14, 27 December 2014
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	[[Image:Inlets_03_SurfSal_icw_big.png\|200px\|right\|thumb\|v.surf.icw interpolating around barriers]]		[[Image:Inlets_03_SurfSal_icw_big.png\|200px\|right\|thumb\|v.surf.icw interpolating around barriers]]

	* Inverse distance weighted average ({{wikipedia\|Inverse_distance_weighting\|IDW}}) interpolation ({{cmd\|v.surf.idw}}, {{cmd\|r.surf.idw}}, and {{~~cmd~~\|r.surf.idw2}})		* Inverse distance weighted average ({{wikipedia\|Inverse_distance_weighting\|IDW}}) interpolation ({{cmd\|v.surf.idw}}, {{cmd\|r.surf.idw}}, and {{AddonCmd\|r.surf.idw2\|version=7}} Addon)
	* Interpolating from contour lines ({{cmd\|r.surf.contour}}), see [[Contour lines to DEM]]		* Interpolating from contour lines ({{cmd\|r.surf.contour}}), see [[Contour lines to DEM]]
	* Interpolating using {{wikipedia\|Natural_neighbor}} method ({{AddonCmd\|r.surf.nnbathy}})		* Interpolating using {{wikipedia\|Natural_neighbor}} method ({{AddonCmd\|r.surf.nnbathy}})

Neteler: +Binning

2014-10-24T09:43:03Z

+Binning

← Older revision		Revision as of 09:43, 24 October 2014
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	* Create raster maps from vector points with ({{cmd\|v.kernel}})		* Create raster maps from vector points with ({{cmd\|v.kernel}})
	* Inverse distance weighted average ({{wikipedia\|Inverse_distance_weighting\|IDW}}) interpolation ({{cmd\|v.surf.idw}}, {{cmd\|r.surf.idw}}, and {{cmd\|r.surf.idw2}})		* Inverse distance weighted average ({{wikipedia\|Inverse_distance_weighting\|IDW}}) interpolation ({{cmd\|v.surf.idw}}, {{cmd\|r.surf.idw}}, and {{cmd\|r.surf.idw2}})

			=== Binning ===

			While not being a real interpolation method, raster binning generates raster maps from vector points.
			Vector points in XYZ format (CSV or ASCII file) can be rasterized (binning into raster cells) using univariate statistics:
			* see ({{cmd\|r.in.xyz}})

	== Comparing original and interpolated data ==		== Comparing original and interpolated data ==

Neteler: +Heat maps

2014-10-24T09:37:23Z

+Heat maps

← Older revision		Revision as of 09:37, 24 October 2014
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	* Interpolating from vector points with {{wikipedia\|Kriging}} ({{cmd\|v.krige\|version=70}}, GRASS 7+)		* Interpolating from vector points with {{wikipedia\|Kriging}} ({{cmd\|v.krige\|version=70}}, GRASS 7+)
	* Interpolating from vector points around barriers or cost surfaces ({{AddonCmd\|v.surf.icw}})		* Interpolating from vector points around barriers or cost surfaces ({{AddonCmd\|v.surf.icw}})

			=== Heat maps (kernel density) ===
			* Create raster maps from vector points with ({{cmd\|v.kernel}})
			* Inverse distance weighted average ({{wikipedia\|Inverse_distance_weighting\|IDW}}) interpolation ({{cmd\|v.surf.idw}}, {{cmd\|r.surf.idw}}, and {{cmd\|r.surf.idw2}})

	== Comparing original and interpolated data ==		== Comparing original and interpolated data ==

Neteler: /* See also */

2014-06-25T13:19:24Z

← Older revision		Revision as of 14:57, 12 October 2020
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	[[Image:Inlets_03_SurfSal_icw_big.png\|200px\|right\|thumb\|v.surf.icw interpolating around barriers]]		[[Image:Inlets_03_SurfSal_icw_big.png\|200px\|right\|thumb\|v.surf.icw interpolating around barriers]]

	* Inverse distance weighted average ({{wikipedia\|Inverse_distance_weighting\|IDW}}) interpolation ({{cmd\|v.surf.idw}}, {{cmd\|r.surf.idw}}, and {{~~AddonCmd~~\|r.fill.~~gaps\|version=7~~}} ~~Addon~~)		* Inverse distance weighted average ({{wikipedia\|Inverse_distance_weighting\|IDW}}) interpolation ({{cmd\|v.surf.idw}}, {{cmd\|r.surf.idw}}, and {{cmd\|r.fill.stats}})
	* Interpolating from contour lines ({{cmd\|r.surf.contour}}), see [[Contour lines to DEM]]		* Interpolating from contour lines ({{cmd\|r.surf.contour}}), see [[Contour lines to DEM]]
	* Interpolating using {{wikipedia\|Natural_neighbor}} method ({{AddonCmd\|r.surf.nnbathy}})		* Interpolating using {{wikipedia\|Natural_neighbor}} method ({{AddonCmd\|r.surf.nnbathy}})
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	Sometimes no-data areas in raster maps (continuous surfaces) needs to be filled using interpolation:		Sometimes no-data areas in raster maps (continuous surfaces) needs to be filled using interpolation:
	* see {{cmd\|r.fillnulls}}		* see {{cmd\|r.fillnulls}}
	* {{~~AddonCmd~~\|r.fill.~~gaps\|version=7~~}}		* see {{cmd\|r.fill.stats}} (IDW based, very fast)

	Optionally extra raster sample points can be generated from an auxiliary raster maps using {{cmd\|r.random}}, merged into the target raster maps with {{cmd\|r.patch}} and then filled using interpolation with {{cmd\|r.fillnulls}}.		Optionally extra raster sample points can be generated from an auxiliary raster maps using {{cmd\|r.random}}, merged into the target raster maps with {{cmd\|r.patch}} and then filled using interpolation with {{cmd\|r.fillnulls}}.

← Older revision		Revision as of 21:18, 19 September 2020
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	[[Image:Inlets_03_SurfSal_icw_big.png\|200px\|right\|thumb\|v.surf.icw interpolating around barriers]]		[[Image:Inlets_03_SurfSal_icw_big.png\|200px\|right\|thumb\|v.surf.icw interpolating around barriers]]

	* Inverse distance weighted average ({{wikipedia\|Inverse_distance_weighting\|IDW}}) interpolation ({{cmd\|v.surf.idw}}, {{cmd\|r.surf.idw}}, and {{AddonCmd\|r.~~surf~~.~~idw2~~\|version=7}} Addon)		* Inverse distance weighted average ({{wikipedia\|Inverse_distance_weighting\|IDW}}) interpolation ({{cmd\|v.surf.idw}}, {{cmd\|r.surf.idw}}, and {{AddonCmd\|r.fill.gaps\|version=7}} Addon)
	* Interpolating from contour lines ({{cmd\|r.surf.contour}}), see [[Contour lines to DEM]]		* Interpolating from contour lines ({{cmd\|r.surf.contour}}), see [[Contour lines to DEM]]
	* Interpolating using {{wikipedia\|Natural_neighbor}} method ({{AddonCmd\|r.surf.nnbathy}})		* Interpolating using {{wikipedia\|Natural_neighbor}} method ({{AddonCmd\|r.surf.nnbathy}})

← Older revision		Revision as of 10:52, 4 December 2018
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	== Resampling methods and interpolation in GRASS ==		== Resampling methods and interpolation in GRASS GIS ==

	=== Reinterpolation of "filled" raster maps (continuous data) to a different resolution ===		=== Reinterpolation of "filled" raster maps (continuous data) to a different resolution ===
Line 7:		Line 7:
	* {{cmd\|r.resamp.interp}} Resampling with nearest neighbor, bilinear, and bicubic method: method=nearest uses the same algorithm as {{cmd\|r.resample}}, but not the same code, so it may not produce identical results in cases which are decided by the rounding of floating-point numbers. For {{cmd\|r.resamp.interp}} method=bilinear and method=bicubic, the raster values are treated as samples at each raster cell's centre, defining a piecewise-continuous surface. The resulting raster values are obtained by sampling the surface at each region cell's centre. As the algorithm only interpolates, and doesn't extrapolate, a margin of 0.5 (for bilinear) or 1.5 (for bicubic) cells is lost from the extent of the original raster. Any samples taken within this margin will be null.		* {{cmd\|r.resamp.interp}} Resampling with nearest neighbor, bilinear, and bicubic method: method=nearest uses the same algorithm as {{cmd\|r.resample}}, but not the same code, so it may not produce identical results in cases which are decided by the rounding of floating-point numbers. For {{cmd\|r.resamp.interp}} method=bilinear and method=bicubic, the raster values are treated as samples at each raster cell's centre, defining a piecewise-continuous surface. The resulting raster values are obtained by sampling the surface at each region cell's centre. As the algorithm only interpolates, and doesn't extrapolate, a margin of 0.5 (for bilinear) or 1.5 (for bicubic) cells is lost from the extent of the original raster. Any samples taken within this margin will be null.
	* {{cmd\|r.resamp.rst}} Regularized Spline with Tension (RST) interpolation 2D: Behaves similarly, i.e. it computes a surface assuming that the values are samples at each raster cell's centre, and samples the surface at each region cell's centre.		* {{cmd\|r.resamp.rst}} Regularized Spline with Tension (RST) interpolation 2D: Behaves similarly, i.e. it computes a surface assuming that the values are samples at each raster cell's centre, and samples the surface at each region cell's centre.
			* {{cmd\|r.resamp.bspline}} resamples with bicubic or bilinear spline interpolation with Tykhonov regularization.
	~~Only GRASS 7:~~		* {{cmd\|r.resamp.filter}} resamples raster map layers using an analytic kernel. It offers box, bartlett, gauss, normal, hermite, sinc, lanczos1, lanczos2, lanczos3, hann, hamming, and blackman kernels.
	* {{cmd\|r.resamp.bspline~~\|version=70~~}} resamples with bicubic or bilinear spline interpolation with Tykhonov regularization.
	* {{cmd\|r.resamp.filter~~\|version=70~~}} resamples raster map layers using an analytic kernel. It offers box, bartlett, gauss, normal, hermite, sinc, lanczos1, lanczos2, lanczos3, hann, hamming, and blackman kernels.

	==== Resampling of raster maps to coarser resolution ====		==== Resampling of raster maps to coarser resolution ====
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	* Interpolating from vector points with {{wikipedia\|B-spline}}s ({{cmd\|v.surf.bspline}})		* Interpolating from vector points with {{wikipedia\|B-spline}}s ({{cmd\|v.surf.bspline}})
	* Interpolating from vector points with regularized splines with tension ({{cmd\|v.surf.rst}} and {{cmd\|v.vol.rst}}), see also [[RST Spline Surfaces]]		* Interpolating from vector points with regularized splines with tension ({{cmd\|v.surf.rst}} and {{cmd\|v.vol.rst}}), see also [[RST Spline Surfaces]]
	* Interpolating from vector points with {{wikipedia\|Kriging}} ({{cmd\|v.krige~~\|version=70~~}}~~, GRASS 7+~~)		* Interpolating from vector points with {{wikipedia\|Kriging}} ({{cmd\|v.krige}})
	* Interpolating from vector points around barriers or cost surfaces ({{AddonCmd\|v.surf.icw}})		* Interpolating from vector points around barriers or cost surfaces ({{AddonCmd\|v.surf.icw}})

Line 47:		Line 45:

	* Statistical assessment: Use {{cmd\|r.mapcalc}} to calculate a differences map, then {{cmd\|r.univar}} to calculates univariate statistics of the differences		* Statistical assessment: Use {{cmd\|r.mapcalc}} to calculate a differences map, then {{cmd\|r.univar}} to calculates univariate statistics of the differences
	* Graphical comparison {{cmd\|g.gui.mapswipe~~\|version=70~~}} - Interactively compares two maps by swiping a visibility bar.		* Graphical comparison {{cmd\|g.gui.mapswipe}} - Interactively compares two maps by swiping a visibility bar.

	== See also ==		== See also ==

← Older revision		Revision as of 22:14, 27 December 2014
Line 19:		Line 19:
	[[Image:Inlets_03_SurfSal_icw_big.png\|200px\|right\|thumb\|v.surf.icw interpolating around barriers]]		[[Image:Inlets_03_SurfSal_icw_big.png\|200px\|right\|thumb\|v.surf.icw interpolating around barriers]]

	* Inverse distance weighted average ({{wikipedia\|Inverse_distance_weighting\|IDW}}) interpolation ({{cmd\|v.surf.idw}}, {{cmd\|r.surf.idw}}, and {{~~cmd~~\|r.surf.idw2}})		* Inverse distance weighted average ({{wikipedia\|Inverse_distance_weighting\|IDW}}) interpolation ({{cmd\|v.surf.idw}}, {{cmd\|r.surf.idw}}, and {{AddonCmd\|r.surf.idw2\|version=7}} Addon)
	* Interpolating from contour lines ({{cmd\|r.surf.contour}}), see [[Contour lines to DEM]]		* Interpolating from contour lines ({{cmd\|r.surf.contour}}), see [[Contour lines to DEM]]
	* Interpolating using {{wikipedia\|Natural_neighbor}} method ({{AddonCmd\|r.surf.nnbathy}})		* Interpolating using {{wikipedia\|Natural_neighbor}} method ({{AddonCmd\|r.surf.nnbathy}})

← Older revision		Revision as of 13:19, 25 June 2014
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	* GRASS {{cmd\|rasterintro}}		* GRASS {{cmd\|rasterintro}}
	* GRASS {{cmd\|vectorintro}}		* GRASS {{cmd\|vectorintro}}
			* [[Import XYZ]]
			* [[Grid registration]]

	[[Category: Documentation]]		[[Category: Documentation]]
	[[Category: FAQ]]		[[Category: FAQ]]
	[[Category: Interpolation]]		[[Category: Interpolation]]