Symbolic package: Difference between revisions

Symbolic package (edit)

1,126 bytes added , 22 April 2017

Anonymous user

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+</source>
+<source lang="octave">
+##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))
 </source>