2D Plotting

Plotting y=f(x) on the interval [-.1,.1]:

First create a vector of (e.g.) 200 equally spaces values between -.1 and .1.

x1=linspace(-.1,.1,200);

Suppose f(x) is an algebraic expression of standard functions such as f(x)= x^2*sin(1/x).

Then the following computes the y values from the x values.

y1 = x1 .^ 2 .* sin(1 ./ x1);

Now put up the plot:

plot(x1,y1)

Adding Additional Graphs

can be accomplished by

x2=linspace(-.1,.1,50);

(Note that this function oscillates less, so we take a coarser grid with only 50 points.

y2 = x2 .^2

y3 = -x2 .^2

plot(x1,y1,x2,y2,x2,y3)

Last Update: September 17, 1998

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