# Matrix Update (Hermitian » Rank-k) (G Dataflow)

Last Modified: June 25, 2019

Calculates the rank-k update of the upper or lower triangular component of a Hermitian matrix.  ## operation A

Operation this node performs on A.

Name Value Description
Direct 0 op(A) = A
Conjugated and Transposed 1 op(A) = conjugate transpose of A
Transposed 2 op(A) = transpose of A

Default: Direct ## A

Matrix such that op(A) has dimensions N × K. ## C

Hermitian matrix.

C must have dimensions greater than or equal to N × N, where N is the number of rows in op(A). If C is an empty matrix, this node initializes C to be an N × N matrix with all elements set to 0.

This node updates the first N rows and N columns of the upper or lower triangular component of C, depending on the value you wire to matrix C type. ## matrix C type

Triangular component of C this node uses for the calculation.

Name Value Description
Lower Triangular 2 This node uses the lower triangular component of C for the calculation.
Upper Triangular 3 This node uses the upper triangular component of C for the calculation.

Default: Upper Triangular ## 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 ## alpha

Scalar that scales op(A) * op(A)H, where op(A)H represents the conjugate transpose of op(A).

Default: 1 ## beta

Scalar that scales C.

Default: 1 ## zherk

Matrix of the same dimensions as C.

For the elements in the first N rows and N columns of the triangular component you select in matrix C type, zherk returns the results of alpha * op(A) * op(A)H +beta * C. For any remaining elements, zherk returns the value of the element with the same index in C. ## 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.

Where This Node Can Run:

Desktop OS: Windows

FPGA: Not supported

Web Server: Not supported in VIs that run in a web application