UPSD

User subroutine to define the frequency dependence for random response loading.

User subroutine UPSD:

• will be called once for each frequency at which calculations will be made during a random response analysis if the frequency function is defined in a user subroutine;

• is used to define complicated frequency dependencies for the cross-spectral density matrix of the random loading; and

• ignores any data given for the associated frequency function outside the user subroutine.

The following topics are discussed:

• User subroutine interface
• Variables to be defined
• Variables passed in for information