# Eric's Matlab Stuff

Stuff here includes matlab code for truss and frame structural
analysis, and code to rotate any matlab plot using the mouse. Actually,
the frame and truss analysis are all from the same set of code, cause
it's pretty much the same thing. There are three structure definitions, a
simple
truss, a simple
frame, and a not so simple
bicycle wheel Warning! Some of the
code is commented better than other parts.

To understand and use those scripts, you really need to look at the
code that does the solution of the frame/truss problem. Each of the
definitions calls the function
solve_truss.m (or a more refined version solve_truss_lu.m that uses lu
factorization.) This function assembles the global stiffness matrix by
calling assemble_k.m, then assembles
the loads by calling
assemble_loads.m. While doing it's job,
assemble_k.m uses the following functions:
trussk.m, beam_k.m,
beam_nst.m, tensor.m, and column.m

After solving the structure, you can
plot the results with the plot_truss.m
function. You can also find
out the forces in the members with the
forces.m function.

Plot_truss.m uses a cool
rotation function, called setup_rotate.m
. This function, along with two helpers
alternate_az.m and alt_az.m allow you
to click on any matlab plot (version 4.2 or later I think) and perform a
free rotate on it. Moving the mouse vertically controls the viewing
altitude and moving horizontally controls the azimuth angle. Clicking
again stops the rotation.

### Finite Element HW

The homework 2 truss problem input file
for the above solving routines.

This page and all contents are © Eric Soroos 1995-6
(soroos@u.washington.edu)