ISE 536–Fall03: Linear Programming and Extensions
November 19, 2003
Lecture 21: Interior Point Methods
Lecturer: Fernando Ord´
o˜nez
1
Complexity of LP
The Klee-Minty example says:
To measure the efficiency of an algorithm, we need:
•
Size of an instance.
For example, consider the LP:
min
c
t
x
s
.
t
.
Ax
=
b
x
≥
0
Size is:
•
Count number of elementary operations, (use
O
(
·
) notation to simplify the count.)
For example, the number of operations of the simplex method in the Klee-Minty
example is:
What about the number of operations of the simplex method in the Klee-Minty ex-
ample if we start from point (1
, . . . ,
1)?
Two instances of the same size can have different running times!
We need:
Worst Case
running time of algorithm
A
: The maximum running time of
A
for instances of a given size.
1
This
preview
has intentionally blurred sections.
Sign up to view the full version.
For example: The worst running time over all LPs with
n
variables,
m
constraints.
Worst-case complexity of the Simplex Method?
Is there and algorithm that is polynomial for LP?

This is the end of the preview.
Sign up
to
access the rest of the document.
- Spring '05
- YY
- Analysis of algorithms, ellipsoid algorithm, min cT, Ellipsoid method
-
Click to edit the document details