Next, we must make f from a symbolic expression into a vectorized function, since it must operate on our arrays of x- and y-values. Note the use of the semicolon! If we had not suppressed the output, MATLAB The command creates a grid with both the x and y coordinates varying in steps of. We use X1 and Y1, rather than x and y, because we want to reserve the latter for symbolic variables. We start by defining the coordinate grid with the meshgrid command. In this case, the parameters are also the x and y coordinates. We will illustrate how this works to plot the graph of the function f above. Thus for aĬurve, the arguments are usually linear arrays, or vectors, while for a surface, they are rectangular arrays, or matrices. The entries give the coordinates as functions of the parameters (which may be identical with the coordinates). The positions in these arrays correspond to parameter or coordinate values The arguments to a MATLAB plotting function, suchĪs surf, plot, plot3, mesh, or contour, are two or three identically shaped arrays. We begin with a brief discussion of how MATLAB does its plotting. Values of the function, and red denoting the largest. Note that MATLAB again color-codes the output, with blue denoting the smallest Two variables is a surface, but not conversely. Graph is a surface, in other words, a two-dimensional geometric object sitting in three-space. Once you execute this command, you can rotate the figure in space to be able to view it from different angles. We will see later why this is so and how to detect it.īut for the time being let's move on. One of the pictures in this case is misleading the contour in dark blue in the very middle should really have The color coding in the contour plot tells us how the values of the constant c are varying. All we need as arguments to ezcontour are the expression, whose contours are to be plotted, and the ranges of values for x and y. (In other words, it is not necessary to use an M-file or an anonymousįunction as an input to the plotting command.)į=((x^2-1)+(y^2-4)+(x^2-1)*(y^2-4))/(x^2+y^2+1)^2 Note that our plotting commands can take as input an expression that defines a function, rather than a function itself. We will take f sufficiently complicated to be of some interest. We begin by illustrating how to produce these two kinds of pictures in MATLAB, using MATLAB's easy-to-use plotting commands,Įzcontour and ezsurf. the graph of the function, which is the set of points (x, y, z) in three-dimensional space satisfying f(x, y) = z.a contour plot, or a two-dimensional picture of the level curves of the surface, which have equations of the form f(x, y) = c, where c is a constant.Refer to Help>Quick Reference for basic Getting Started tips. Solve an Ordinary Differential Equation? Learn more about available tools and features, such as palettes and the context panel. topics cover the essentials for doing mathematics in Maple. ĭrag the expression sin x 2 onto the existing plot of sin x. You can also combine multiple plots using drag and drop.Įxample: Combining the Plots for sin x and sin x 2Ĭlick sin(x) and, from the context panel, choose Plots > 2-D Plot. If you select Show Command in the right panel, you can see the underlying command used to create this plot. The plot is shown in the main window, and in the Plot Builder window you can change options. Type the following, and from the Context Panel, select Plot Builder : Here is the first from the previous section.Įxample: Using Plot Builder to Plot Two Expressions You can use the Plot Builder from the Context Panel to plot a list or sequence of expressions. The plots:-display command also works on 3-D plots: Plot2 ≔ plot cos, color = Niagara Green : Plot2 := plot(cos, color="Niagara Green"): You can also combine multiple plot structures and display these together using the plots:-display command:Įxample: Plotting Multiple Plot Structures Together Note: In Maple, a list is denoted using square brackets.Įxample: Plotting Sine and Cosine on Same PlotĮxample: Plotting x, x 2 with Custom Color The following examples with the plot command provide a list of expressions to plot.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |