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I have been trying to grid a point cloud, version1.2, LiDAR datasets which are intended to be used for hydraulic simulation of flood propagation. Already, I have used Arc* to work on the traditional (.las) format, to create lasdataset. Then, a raster dataset was created from the lasdataset and finally interpolated by means of a nearest neighbour algorithm. The interpolated raster data were exported as txt files.

Having gone through this routine, I expected a result with header file as well as regular values in X, Y and Z orthogonality. Instead, the result I got was distorted sets of (real) numbers I could not make sense of. I tried using Surfer* to grid txt files created from (.las) point clouds, by means of lastools*, but the result was a binary file and I couldn’t read it. Lastools* gave a reasonable result when used to grid the point clouds, only that the cell size varies inversely with the number of cells that result in the output grid.

My challenge is how to grid the point cloud LiDAR and specify the number of rows and columns to be contained in the resulting gridded data, giving a fixed cell size.

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  • Is there a reason to suspect that there is a regular grid pattern in the dataset? Have you tried to create a fishnet (in Arc*) then convert to centroids to get a regular grid? – user681 Jul 9 '14 at 15:48
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    Welcome to GIS.SE I see you're new here. Please take a look at our tour and help to guide you in asking better questions. As it stands, you're post isn't informative enough. What have you tried? Why did they not satisfy your demands. Thanks gis.stackexchange.com/tour – GISKid Jul 9 '14 at 15:49
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    Are you referring to a tessellation of n-dimensional Euclidean space by congruent parallelotopes (e.g. bricks) or simply raster format? – Aaron♦ Jul 9 '14 at 15:49
  • What is it that you're after LAS, raster or XYZ? I'm not sure what you mean by 'grid lidar' the term grid is ambiguous. Please elaborate on what output you're expecting to get from this (with an example would be nice). – Michael Stimson May 3 '16 at 22:12
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The output from 'LAS Dataset to Raster' or the appropriate LasTool, should be sufficient for your purposes - there is not usually a need to specify rows and columns as the interpolation functions figure that out for you. Cell size won't vary within a single raster so that part of the question is confusing. What is the destination of the products produced as a grid? The documentation might help you/us determine what you need.

Notably, you shouldn't need to create a grid from a grid - this is pointless and the interpolation functions by ArcGIS or LasTools should be sufficient on their own, without invoking Surfer.

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