There's a lot in Manifold, I agree. But it's like most things in that if you take one step at a time you can cover a lot of ground. LiDAR data is point data. It's not continuous data, it's just a lot of points. When you zoom out, sure, it looks tightly packed, but when you zoom in those points can seem far apart from each other. What's in between? The LiDAR data doesn't say. Kriging just converts a scattering of points into a surface, interpolating in a reasonable way to fill in the surface in between LiDAR points, and also interpolating in a reasonable way to create an evenly-spaced raster where LiDAR points are not necessarily evenly spaced. The topic I suggested has a biographical sketch of Krige and how he came to invent the technique named after him. Krige was dealing with natural resource exploration, where he had a scattering of drill holes that sampled what was underground, and he needed to interpolate between those locations to try to figure out how an ore body was laid out underground, so he came up with the statistical interpolation method now called Kriging. Once you have a surface, you can create contour lines on that surface. So, the process is: LiDAR drawing -> Surface made with Kriging -> Drawing of contour lines You might ask, why doesn't Manifold provide a command that collapses those two steps into one? The answer is to give people simpler ways of getting the big flexibility they want. Kriging isn't just used for the sole and exclusive purpose of making surfaces from LiDAR points that will be used for contours. It's used in a huge range of different circumstances. So there's a Kriging facility that works well for all of those. Likewise, contours aren't just generated on surfaces created by Kriging from LiDAR data. Contours are created from a very wide range of different surfaces that have been created in different ways from many different types of data. So there's a contours tool for that. Using the two commands in sequence allows enormous variability and flexibility. For example, you might want your LiDAR data as a surface not for contouring but for other purposes, such as creating hill shaded terrain elevation displays. By providing a large, but comparatively limited, set of general purpose commands that can be combined and re-combined as you like, you can do millions of different things exactly as you prefer. In contrast, by having a special purpose command for each possible path people want to take, you end up with millions of special purpose commands that nobody will ever be able to learn or use (if even it were practical to create a special command for each possible pathway or task somebody might want to do with a GIS). There really isn't all that much to learn in Manifold - it's not like learning, say, French, where you need to memorize about 3000 core vocabulary verbs, nouns and adjectives, plus about 100 core rules for grammar and around 1000 irregularities. In contrast, Manifold has about a dozen major dialogs and, for most GIS work, only about 50 key commands that are highly regular and which cover almost all work, and none of which needs to be memorized, since they are always at hand in menus or transform templates. That can be learned in about four days of attentive study. SQL - not required, but a great assistant when you want it - at the simple level used in GIS can easily be learned in another two days of attentive study. Where people get it wrong is they fail to invest a day or two into serious study - and I mean a full eight hour day of attention, not seven hours of walking around, having lunch and checking emails - into getting the very fundamentals down. Do that, build a sound foundation of the basics, and all the rest falls into place very quickly.
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