MA/CS 371 - Lab 4
MA/CS 371 - Lab 4
Numerical Integration - Upper and Lower Sums and the Trapezoid Rule
Section 1: Introduction
The goal of this lab is to introduce you to:
- Practical implementation of upper and lower sums
- Practical implementation of the trapezoid rule
- formatted output with fprintf
If you have not already done so, create a directory for this lab and
copy the lab 4 files into it. If you start off in your home directory you
can do the following:
cp ~cs371/lab4/* .
and (as always) don't forget to type that last period.
Section 2: Topics for Lecture
This time I'm going to briefly lecture about some of the formatting
options available with MATLAB's fprintf command. This command
behaves pretty much the same in MATLAB as it does in C. I'll show you
the overall idea and explain a few of the simpler types.
Section 3: Upper and Lower Sums
The file sums.m is a bare skeleton which you will fill out into
a program which computes approximations to a particular integral via
the upper and lower sums method.
The function we will be approximating will be
| 1 - sin(x) dx
The vector q in the program indicates the number of
subintervals to use for each approximation. The MATLAB statement
runs through the loop length(q) times, setting i to q(1) the first
time, q(2) the second time, etc.
Complete the program sums.m and answer the first two questions.
Section 4: The Trapezoid Rule
The file trap.m is a bare skeleton which you will fill out into
a program which approximates the above function by the trapezoid rule.
Complete the program trap.m and answer the next two questions.
Section 5: Submitting Your Work
When your programs sums.m and trap.m are ready, run
I will accept solutions through 11:59pm Thursday.
As before, I would prefer that you e-mail me the answers to the
problems but there will be a few hard copies in lab.