Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Matlab for loops involving matrix

  1. Oct 24, 2012 #1
    Given the following system of equations
    3x1 + ax2 = 1
    ax1 + 4x2 = 0

    where -pi ≤ a ≤ pi. We would like to find out the range of values of x1 and x2 that are observed as a is varied. Do this as follows:

    1. Create a for loop that uses the variable a as the indexing value, varied from over the
    specified range in increments of 0.2.
    2. For each value of a, solve the above system by using the RREF function.
    3. Also for each value of a, plot the values of x1 and x2 against the corresponding value of a
    for each loop iteration (i.e. the coordinate pairs (a,x1) and (a,x2)). Include a legend in
    your final plot! See MATLAB help for more details.
    4. From the plot, determine the range of values for x1 and x2. You may use the data cursor
    tool to pick off values from the plot.

    I understand and have completed step 1. However I don't know how to assign each new a to a variable that can be plugged into the matrix for step 2. Right now my for loop looks like:

    i=0.2;
    for a=-1*pi:i:pi,
    a
    end
     
  2. jcsd
  3. Oct 25, 2012 #2

    jasonRF

    User Avatar
    Science Advisor
    Gold Member

Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook