C_GetFrequencyDomainResultsProcess

Call C_GetFrequencyDomainResultsProcess to extract frequency domain results expressed as a process. The model must use the frequency domain dynamics solution method and be in the simulation complete state.

A process is specified by an array of results process components. Each results process component is a harmonic represented as a complex number z_i, where i is the component index. The results process components are in one-to-one correspondence with the model process components, as returned by C_GetFrequencyDomainProcessComponents.

The results process component is defined as follows:

• The frequency is the same as the corresponding model process component.
• The amplitude is equal to √2.|z_i|.
• The phase lead is given by arg z_i.

The phase definition is dependent on the process type of the model process component that the results process component is associated with:

• For ProcessType iptWave, it is the phase lead relative to the wave component's crest at the global origin.
• For ProcessType iptWind, it is the phase lead relative to the wind component's peak velocity.
• For ProcessType iptWaveDrift, it does not define the phase lead relative to some physical feature of the environmental system, unlike the other process types. However, it allows the phase lead of the different result variables (or the same result variable at different model coordinates) to be defined relative to each other.

In practise, knowledge of these conventions is often not required. In typical usage the process will be linearly combined with other processes and then passed to C_GetFrequencyDomainResultsFromProcess, C_GetFrequencyDomainSpectralDensityGraphFromProcess or C_GetFrequencyDomainSpectralResponseGraphFromProcess for further processing. That usage pattern does not require any knowledge of the conventions outlined above.

Parameters

ObjectHandle (IN)

The handle of the object for which you want frequency domain results.

lpObjectExtra (IN)

Points to a TObjectExtra2 variable which specifies where on the object results are required. Can be NULL if no additional information is needed.

VarID (IN)

Specifies the OrcaFlex variable for which the time history results are requested. Call C_GetVarID to obtain a VarID from a variable name.

lpComponentCount (OUT)

Points to a variable in which the number of components is returned.

lpProcess (OUT)

Points to an array of complex numbers in which the process will be returned.

It is the caller's responsibility to allocate (and deallocate) the memory pointed to by lpProcess. To find out how much memory to allocate call C_GetFrequencyDomainResultsProcess passing NULL as the lpProcess parameter and use the value returned in lpComponentCount to determine how much memory to allocate. The array must be of length *lpComponentCount.

lpStatus (OUT)

Points to a variable in which the status result for the function call will be returned.

Unicode and ANSI

The Unicode function name is C_GetFrequencyDomainResultsProcessW and the ANSI function name is C_GetFrequencyDomainResultsProcessA.

See also

C_GetFrequencyDomainResults, C_GetFrequencyDomainResultsFromProcess, C_GetFrequencyDomainSpectralDensityGraphFromProcess, C_GetFrequencyDomainSpectralResponseGraphFromProcess.