99
edits
Symbolic package: Difference between revisions
Jump to navigation
Jump to search
m
→Demos and usage examples: proofread a new example: fix typos and style
WARDEVIL UFO (talk | contribs) |
m (→Demos and usage examples: proofread a new example: fix typos and style) |
||
| Line 50: | Line 50: | ||
<source lang="octave"> | <source lang="octave"> | ||
##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. | ## 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. | ## Make sure symbolic package is loaded and symbolic variables declared. | ||
pkg load symbolic | pkg load symbolic | ||
syms x y | syms x y | ||
##Write a Vector Field Equation in terms of symbolic variables | ## Write a Vector Field Equation in terms of symbolic variables | ||
vectorfield = [sin(pi*y/2); -sin(pi*x/2)]; | |||
##Vector components are converted from | ## Vector components are converted from symbolic into "anonymous functions" which allows them to be graphed. | ||
## The "'vars', [x y]" syntax ensures each component is a function of both 'x' & 'y' | |||
##The " 'vars', [x y]" syntax | iComponent = function_handle (vectorfield(1), 'vars', [x y]); | ||
iComponent = function_handle ( | jComponent = function_handle (vectorfield(2), 'vars', [x y]); | ||
jComponent = function_handle ( | |||
## | ## Setup a 2D grid | ||
[X,Y] = meshgrid([-.5:.05:.5]); | [X,Y] = meshgrid ([-0.5:0.05:0.5]); | ||
figure | figure | ||
quiver(X,Y,iComponent(X,Y),jComponent(X,Y)) | quiver (X, Y, iComponent (X, Y), jComponent (X,Y)) | ||
</source> | </source> | ||