Mathematica Tutor

Part 8: Graphing Functions

1. Let's plot 3 sin(2x) over the interval [0,2 pi]. Enter
   Plot[3*Sin[2*x], {x, 0, 2*Pi}];
   We can obtain the same result by defining the function f given by
   f(x) = 3 sin(2x)

   and plotting f(x). Enter the following:
   f[x_]:= 3*Sin[2*x]
   Plot[f[x], {x, 0, 2*Pi}];
   
   

2. When the plot appears, use your mouse to "select" it -- you should see a box around the graphic. Experiment with the drag buttons at the corners and sides of the box.
   
   
3. Next we plot data given as ordered pairs. Enter
   data={{0,1},{2,2},{4,6},{5,1}}
   Then enter
   ListPlot[data, PlotStyle->PointSize[.02]];
   Go back and see what happens if you delete "PlotStyle->PointSize[.02]."
   
   
4. Often we wish to view several graphs at the same time. One way to do this is to enter the desired plots directly into the plot command. Enter
   Plot[{Sin[x],Cos[x]}, {x, 0, 2*Pi}, PlotStyle->{RGBColor[0,1,0], RGBColor[0,0,1]}];
   
   
5. Another way to create multiple plots is to use the Show command. Enter
   graph1=Plot[Sin[x], {x, 0, 2*Pi}, PlotStyle->RGBColor[0,1,0]];
   This creates a plot and names it "graph1."

   Create a second plot by entering
   graph2=Plot[Cos[x],{x, 0, 2*Pi}, PlotStyle->RGBColor[0,0,1]];
   

   To see both plots together, enter
   Show[graph1,graph2];