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I've been working through the Elementary Introduction to the Wolfram Langauge book on the Wolfram website. Chapter 24, on "More Forms of Visualization" has an example of using `ListPlot3D` with `&[GeoElevationData][1]` to yield a 3-dimensional view...
I'm struggling to understand why Mathematica 13.1 gives multiple linear regression coefficients that are greatly different from the Data Analysis package in Excel and Maple's LinearFit function. I'm assisting a colleague who is using Excel to find...
I am using Piecewise with conditions based on whether x is a rational number or not. The function assignment seems to work. But when I plot it, an empty plot shows up (though the PlotLabel looks nice). Clear[f]; f[x_] := Piecewise[{{x,...
I'm working on a problem from an old textbook that involves composite functions, domains, and equalities that are valid within a given domain. After being given f(x)=1/(1-x), I'm asked to find the domain of a composite function, as shown here: ...
I am reviewing my old calculus book from college, Calculus and Analytic Geometry, 4th Ed. (by Sherman K. Stein). I started a notebook in MMA 10.0.2 to do the problems at the end of each section, if I can. See attached. (Not much there yet because...