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Posted: Sun May 18, 2008 2:27 am
Guest
Hello

Consider the following three kind of matrices. are there any
properties such as inverse or Eigenvalues or determinant or etc
specific to these kind of matrices:

1-In each row the sum of square of each element is 1.

2-In each row the sum of square of each element is 1 And In each
column the sum of square of each element is 1

3-if t1,t2,..,tn are either real or complex numbers we construct the
matrix as follows :
|t1| t1 t1 t1 t1
t1' |t2| t2 t2 t2
t1' t2' |t3| t3 t3
t1' t2' t3' |t4| t4
t1' t2' t3' t4' |t5|


Thank you for your help
Best regards,
Robert Israel...
Posted: Sun May 18, 2008 4:32 pm
Guest
david.aabb at (no spam) gmail.com writes:

Quote:
Hello

Consider the following three kind of matrices. are there any
properties such as inverse or Eigenvalues or determinant or etc
specific to these kind of matrices:

1-In each row the sum of square of each element is 1.

2-In each row the sum of square of each element is 1 And In each
column the sum of square of each element is 1

3-if t1,t2,..,tn are either real or complex numbers we construct the
matrix as follows :
|t1| t1 t1 t1 t1
t1' |t2| t2 t2 t2
t1' t2' |t3| t3 t3
t1' t2' t3' |t4| t4
t1' t2' t3' t4' |t5|

What is ' ? Complex conjugate?

By "sum of square" do you mean "sum of squares of absolute values" in the
complex case?
--
Robert Israel israel at (no spam) math.MyUniversitysInitials.ca
Department of Mathematics http://www.math.ubc.ca/~israel
University of British Columbia Vancouver, BC, Canada
...
Posted: Sun May 18, 2008 7:48 pm
Guest
Quote:
What is ' ?  Complex conjugate?

yes, by t1' I mean complex conjugate for complex numbers or -t1 for
real numbers

Quote:
By "sum of square" do you mean "sum of squares of absolute values" in the
complex case?

yes

On May 19, 12:32 am, Robert Israel
<isr... at (no spam) math.MyUniversitysInitials.ca> wrote:
Quote:
david.a... at (no spam) gmail.com writes:
Hello

Consider the following three kind of matrices. are there any
properties such as inverse or Eigenvalues or determinant or etc
specific to these kind of matrices:

1-In each row the sum of square of each element is 1.

2-In each row the sum of square of each element is 1 And In each
column the sum of square of each element is 1

3-if t1,t2,..,tn are either real or complex numbers we construct the
matrix as follows :
|t1|       t1      t1      t1      t1
t1'        |t2|    t2      t2      t2
t1'        t2'     |t3|    t3      t3
t1'        t2'     t3'     |t4|    t4
t1'        t2'     t3'     t4'     |t5|

What is ' ?  Complex conjugate?

By "sum of square" do you mean "sum of squares of absolute values" in the
complex case?
--
Robert Israel              isr... at (no spam) math.MyUniversitysInitials..ca
Department of Mathematics        http://www.math.ubc.ca/~israel
University of British Columbia            Vancouver, BC, Canada
...
Posted: Mon May 19, 2008 3:57 am
Guest
On May 18, 7:27 am, david.a... at (no spam) gmail.com wrote:
Quote:
Hello

Consider the following three kind of matrices. are there any
properties such as inverse or Eigenvalues or determinant or etc
specific to these kind of matrices:

1-In each row the sum of square of each element is 1.

2-In each row the sum of square of each element is 1 And In each
column the sum of square of each element is 1

3-if t1,t2,..,tn are either real or complex numbers we construct the
matrix as follows :
|t1|    t1      t1      t1      t1
t1'     |t2|    t2      t2      t2
t1'     t2'     |t3|    t3      t3
t1'     t2'     t3'     |t4|    t4
t1'     t2'     t3'     t4'     |t5|

Thank you for your help
Best regards,

I think the eigenvalues are real and less than or equal to 1 since
A`*A is a real symmetric matrix and all values are less than 1. You
should test it out with some examples to make sure I'm correct. I
could be wrong, I'm just working off a vague memory from over 20 years
ago.

Mark
Alois Steindl...
Posted: Mon May 19, 2008 9:08 am
Guest
vontressms at (no spam) cs.com writes:
Quote:


I think the eigenvalues are real and less than or equal to 1 since
A`*A is a real symmetric matrix and all values are less than 1. You
should test it out with some examples to make sure I'm correct. I
could be wrong, I'm just working off a vague memory from over 20 years
ago.

Hello,

it seems you are a little bit too optimistic:
The matrix with all entries = sqrt(1/n) has one eigenvalue sqrt(n).

Alois


--
Alois Steindl, Tel.: +43 (1) 58801 / 32558
Inst. for Mechanics and Mechatronics Fax.: +43 (1) 58801 / 32598
Vienna University of Technology, A-1040 Wiedner Hauptstr. 8-10
 
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