Is A Full Rank Equivalent to an Overdetermined System?

Click For Summary
SUMMARY

An overdetermined system represented by Ax=b can yield a unique approximative solution through least squares when matrix A has full rank. However, having full column rank does not guarantee that a solution x exists such that Ax=b is satisfied exactly. The discussion clarifies that while full rank is a necessary condition for unique solutions, it does not imply that the system is overdetermined in every instance.

PREREQUISITES
  • Understanding of linear algebra concepts, specifically matrix rank
  • Familiarity with overdetermined systems and their properties
  • Knowledge of least squares approximation techniques
  • Experience with solving linear equations
NEXT STEPS
  • Study the properties of full rank matrices in linear algebra
  • Learn about least squares methods and their applications
  • Explore the differences between underdetermined, determined, and overdetermined systems
  • Investigate numerical methods for solving linear systems
USEFUL FOR

Students and professionals in mathematics, engineering, and data science who are dealing with linear systems and optimization problems.

Niles
Messages
1,834
Reaction score
0

Homework Statement


Hi

If I am dealing with an overdetermined system Ax=b, then I can (assuming A has full rank) find the unique approximative solution by least squares.

Now, in my book it says that: "For a full column rank matrix, it is frequently the case that no solution x satisfies Ax=b exactly". I assume the book is saying that A having full rank is equivalent to it being overdetermined.

Is that always the case?


Niles.
 
Physics news on Phys.org
That is not always the case, I found out.
 

Similar threads

  • · Replies 6 ·
Replies
6
Views
3K
  • · Replies 7 ·
Replies
7
Views
3K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 9 ·
Replies
9
Views
5K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 4 ·
Replies
4
Views
3K
Replies
5
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 6 ·
Replies
6
Views
9K
  • · Replies 3 ·
Replies
3
Views
1K