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→Demos and usage examples

ans =

-0.82502 4.20248 -1.57080

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##Demo of how to graph symbolic functions (by converting SYMBOLIC functions into ANONYMOUS functions)

##The following code will produce the same vector field plot as Figure 1.14 from Example 1.6 (pg. 39) from A Student's Guide to Maxwell's Equations by Dr. Daniel Fleisch.

##Make sure symbolic package is loaded and symbolic variables declared.

pkg load symbolic;

syms x y

##Write a Vector Field Equation in terms of symbolic variables

vector = [sin(pi .* y ./2 ); -sin(pi .* x ./2 )];

##Vector components are converted from symoblic into anonymous form which allows them to be graphed

##The '1' & '2', in vector(1) & vector(2) are indeces for the vector.

##The " 'vars', [x y]" syntax tells function_handle that each component is a function of both 'x' & 'y'

iComponent = function_handle (vector(1), 'vars', [x y]);

jComponent = function_handle (vector(2), 'vars', [x y]);

##Setting the Grid up to graph all axes for all variables from -.5 to .5, with spacings .05 apart.

[X,Y] = meshgrid([-.5:.05:.5]);

##Draw the Vector Field!

figure

quiver(X,Y,iComponent(X,Y),jComponent(X,Y))

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