givens - Givens transformation

Calling Sequence

U=givens(xy)

U=givens(x,y)

[U,c]=givens(xy)

[U,c]=givens(x,y)

Parameters

• x,y : two real or complex numbers
• xy : real or complex size 2 column vector
• U : 2x2 unitary matrix
• c : real or complex size 2 column vector

Description

U = givens(x, y) or U = givens(xy) with xy = [x;y] returns a 2x2 unitary matrix U such that:

U*xy=[r;0]=c.

Note that givens(x,y) and givens([x;y]) are equivalent.

Examples

A=[3,4;5,6];
U=givens(A(:,1));
U*A
 

See Also

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