mm245/ma260 lab3

mm245/ma260 lab3

http://www.maths.nuigalway.ie/~gettrick/teach/mm245/labs/l3.html

As well as coming to the supervised lab - you are expected to work on this lab on your own outside of lab hours (in your own time).
For this lab you must submit all source code (matlab/scilab/octave .m files). The code should have comments of explanation, with at least as many comments as code. This should be sent in via BLACKBOARD (not directly by email). Any questions asked should be answered by typing into a plain text (.txt) file (or inserted at the end of MATLAB/SCILAB/OCTAVE code after the percentage (comment) symbol) which should also be uploaded via blackboard.
This material should be uploaded before the deadline of 5pm Friday October 25th, 2013. You will lose 20% for each day (or part of day) the lab is late.
Plagiarism (the unattributed copying of work from other sources (internet, fellow students,....)) will not be tolerated. Please see http://www.nuigalway.ie/engineering/documents/plagiarism_guide_students _v4.pdf. You risk getting zero for your lab if it is found to be plagiarized.
If you are really stuck:

Ask in the lab
Post a question in the Discussion Board in BLACKBOARD

Spend 30 minutes familiarizing yourself with polynomials in OCTAVE/SCILAB/MATLAB. You can search online for any of the tutorials or documentation on MATLAB/SCILAB/OCTAVE, or read http://www.engin.umich.edu/group/ctm/basic/basic.html#polynomial or http://www.matrixlab-examples.com/polynomials.html.

You should study (and run) the code in poly1.m at http://www.maths.nuigalway.ie/~gettrick/teach/mm245/labs/matlab/ which is commented to explain its operation.

For this lab Consider the function 3**x - x (for example, for x=2, the y value is 3**2 - 2 = 7). For the x values of 2, 3 and 4:

determine the corresponding y values.

calculate the Lagrange Interpolating polynomial (of degree 2) for these 3 points.

determine the relative error at x=3.5

For the same function, calculate the Lagrange Interpolating polynomial (of degree 1) if we only consider two points x=2 and x=3. Again, calculate the relative error at x=3.5.