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## Re: Syntax question

**From**: |
Heber Farnsworth |

**Subject**: |
Re: Syntax question |

**Date**: |
Sat, 22 Feb 2003 12:34:27 -0600 |

`When you select an element of a Matrix X you say X(r,c) where r and c
``are the row and column you want. The colon ":" is a wildcard in this
``notation. X(r,:) means "the rth row and every column of X" and X(:,c)
``means "every row of the cth column of X.
`
Heber Farnsworth
On Saturday, February 22, 2003, at 12:11 PM, Henry F. Mollet wrote:

*Calculation of left and right eigenvector
*belonging to largest eigenvalue of matrix,
*then matrix/vector multiplication:
[W,d] = eig(a);
d = diag (d);
imax = find (d==max(d));
V = conj(inv(W));
w1 = W(:,imax); /line 5
v1= real (V(imax,:)).'; /line 6
Senmat = v1*w1''
I understand everything except the ":" in lines 5 and 6. Somehow they
instruct to pick the column vector and row vector, respectivly, which go
with the largest eigenvalue. But how does it work?
Henry
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**Syntax question**, *Henry F. Mollet*, `2003/02/22`
**Re: Syntax question**,
*Heber Farnsworth* **<=**