# Givens Rotation (Givens Rotation Parameters) (G Dataflow)

Last Modified: March 15, 2017

Creates the parameters for performing a Givens rotation.

## x

x-component for the two-element vector.

This input accepts the following data types:

• Double-precision, floating-point numbers
• Complex double-precision, floating-point numbers

Default: The default value is 0 if x is a double-precision, floating-point number. The default value is 0+0i if x is a complex double-precision, floating-point number.

## y

y-component for the two-element vector.

This input accepts the following data types:

• Double-precision, floating-point numbers
• Complex double-precision, floating-point numbers

Default: The default value is 0 if y is a double-precision, floating-point number. The default value is 0+0i if y is a complex double-precision, floating-point number.

## error in

Error conditions that occur before this node runs.

The node responds to this input according to standard error behavior.

Standard Error Behavior

Many nodes provide an error in input and an error out output so that the node can respond to and communicate errors that occur while code is running. The value of error in specifies whether an error occurred before the node runs. Most nodes respond to values of error in in a standard, predictable way.

error in does not contain an error error in contains an error
If no error occurred before the node runs, the node begins execution normally.

If no error occurs while the node runs, it returns no error. If an error does occur while the node runs, it returns that error information as error out.

If an error occurred before the node runs, the node does not execute. Instead, it returns the error in value as error out.

Default: No error

## r

x-component after the Givens rotation.

This output can return the following data types:

• Double-precision, floating-point numbers
• Complex double-precision, floating-point numbers

## c

c parameter of the Givens rotation.

## s

s parameter of the Givens rotation.

This output can return the following data types:

• Double-precision, floating-point numbers
• Complex double-precision, floating-point numbers

## error out

Error information.

The node produces this output according to standard error behavior.

Standard Error Behavior

Many nodes provide an error in input and an error out output so that the node can respond to and communicate errors that occur while code is running. The value of error in specifies whether an error occurred before the node runs. Most nodes respond to values of error in in a standard, predictable way.

error in does not contain an error error in contains an error
If no error occurred before the node runs, the node begins execution normally.

If no error occurs while the node runs, it returns no error. If an error does occur while the node runs, it returns that error information as error out.

If an error occurred before the node runs, the node does not execute. Instead, it returns the error in value as error out.

## z

z parameter of the Givens rotation.

You can use this output to reconstruct Givens rotation parameters c and s.

This output can return the following data types:

• Double-precision, floating-point numbers
• Complex double-precision, floating-point numbers

## Algorithm for Calculating Givens Rotation Parameters

This node uses the following equations to calculate Givens rotation parameters:

$\left[\begin{array}{cc}c& s\\ -s& c\end{array}\right]*\left[\begin{array}{c}x\\ y\end{array}\right]=\left[\begin{array}{c}r\\ 0\end{array}\right]$

c2 + s2 = 1

where

• x is the x-component of the two-element vector
• y is the y-component of the two-element vector
• s and c are the Givens rotation parameters

Where This Node Can Run:

Desktop OS: Windows

FPGA: This product does not support FPGA devices