MAP:Cantilever Beam

The Cantilever Beam lab has been a foundation of EGR 103 for several years. It demonstrates how to initialize the workspace, load and manipulate data, perform calculations, generate values of a model equation, plot data and model values, and save plots. Not bad for the second week of an introductory course in computational methods! For at least the short-term, the Cantilever Beam lab will live on in MATLAB and in Python. Since the lab itself actually develops the final code, it is acceptable to post it here. Here's what the lab's solution looks like in MATLAB and in Python 3:

MATLAB

<source lang=matlab> %% Initialize the workspace % Clear all variables clear % Change display to short exponential format format short e

%% Load and manipulate the data % Load data from Cantilever.dat load Cantilever.dat % Copy data from each column into new variables Mass = Cantilever(:,1); Displacement = Cantilever(:,2); % Convert Mass to a Force measurement Force = Mass*9.81; % Convert Displacement in inches to meters Displacement = (Displacement*2.54)/100;

%% Perform calculations % Use polyfit to find first-order fit polynomials P = polyfit(Force, Displacement, 1)

%% Generate predictions % Create 100 representational Force values ForceModel = linspace(min(Force),max(Force),100); % Calculate Displacement predictions DispModel = polyval(P, ForceModel);

%% Generate and save plots % Bring up a figure window figure(1) % Clear the figure window clf % Plot Displacement as a function of Force plot(Force, Displacement, 'ko') % Turn hold on, plot the model values, and turn hold off hold on plot(ForceModel, DispModel, 'k-') hold off % Turn the grid on grid on % Label and title the graph xlabel('Force (Newtons)') ylabel('Displacement (meters)') title('Displacement vs. Force for Cantilever.dat (NetID)') % Save the graph to PostScript print -deps RunCanPlot </matlab>