RCROSS

I/O Options Entry

RCROSS – Output Request

Description

The RCROSS command can be used in the I/O Options section to request computation and output of cross-power spectral density functions for random response analysis.

Format

RCROSS(format_list,form,type,randid=RANDPS_ID) = option

Argument	Options	Description
format	<PUNCH>, blank Default = blank	PUNCH:	Results are output in Nastran punch results format (.pch file).
format	<PUNCH>, blank Default = blank	blank:	Results are output in all active formats for which the result is available.

form	<COMPLEX, REAL, IMAG, PHASE, BOTH> Default = COMPLEX	COMPLEX:	Provides a combined magnitude/phase form of complex output to the .res file if HM output format is chosen. The REAL form of complex output is used for other formats, if they are not specifically defined. (Phase output is in degrees).
		REAL or IMAG:	Provides rectangular format (real and imaginary) of complex output.
		PHASE:	Provides polar format (phase and magnitude) of complex output.
		BOTH:	Provides both rectangular and polar formats of complex output.

type	<PSDF> Default = PSDF	PSDF:	Requests the cross-power spectral density function be calculated and output for random analysis post-processing.

option	<RCROSS_ID>	RCROSS_ID:	Set identification of an RCROSS bulk data entry.

randid	<RANDPS_ID, blank>	RANDPS_ID:	Set identification number of a RANDPS bulk data entry (Comments 3 and 4).

Comments

1.	The RCROSS I/O option must be used in conjunction with the RANDOM subcase information entry.

2.	Response quantities, such as DISPLACEMENT, STRESS and STRAIN, must be requested by corresponding I/O Options in order to compute cross-power spectral density between the two response quantities specified by the RCROSS bulk data entry.

3.	Multiple RCROSS bulk data entries must be defined when each RCROSS subcase information entry references different randid.

For example:

rcross(PUNCH, PHASE, PSDF, randid=210020)=451
rcross(PUNCH, PHASE, PSDF, randid=210050)=452
rcross(PUNCH, PHASE, PSDF, randid=210070)=453
rcross(PUNCH, PHASE, PSDF, randid=210090)=454

4.	randid=<RANDPS_ID> must be specified within the RCROSS I/O options entry, when multiple RANDOM subcase information entries are present.