To configure settings on the Basic tabbed page:

In the Edit Step dialog box, display the Basic tabbed page.

(For information on displaying the Edit Step dialog box, see “Creating a step,” Section 14.9.2, or “Editing a step,” Section 14.9.3.)

In the Description field, enter a short description of what occurs during this analysis step. ABAQUS stores the text that you enter in the output database, and the text is displayed in the state block by the Visualization module.

Select one of the following options:

Select Compute real response only if you want ABAQUS/Standard to ignore damping terms. This option can significantly reduce computational time.

Select Compute complex response if you want to include damping terms and allow a complex system matrix to be factored.

For more information, see “Damping” in “Direct-solution steady-state dynamic analysis,” Section 6.3.4 of the ABAQUS Analysis User's Manual.

Select a Scale option to indicate whether you want the frequency range(s) of interest to be divided using a Logarithmic or Linear scale.

Toggle on Use eigenfrequencies to subdivide each frequency range if you want the frequency range(s) of interest to be subdivided using the system's eigenfrequencies. This option requires a preceding frequency step. For more information, see “Selecting the type of frequency interval for which output is requested” in “Direct-solution steady-state dynamic analysis,” Section 6.3.4 of the ABAQUS Analysis User's Manual.

Enter the following data in the Data table:

Lower Frequency

The lower limit of the frequency range or a single frequency, in cycles/time.

Upper Frequency

The upper limit of the frequency range, in cycles/time. If you enter zero, ABAQUS/Standard assumes that results are required only at the frequency specified in the Lower Frequency column.

Number of Points

The number of points in the frequency range at which results should be given.

If you toggled on Use eigenfrequencies to subdivide each frequency range, this is the number of points at which results should be given, including the end points, from the lower limit of the frequency range to the first eigenfrequency in the range; in each interval from eigenfrequency to eigenfrequency; and from the highest eigenfrequency in the range to the high limit of the frequency range.

If you toggled off Use eigenfrequencies to subdivide each frequency range, this is the total number of points in the frequency range, including the end points.

Bias

The bias parameter. This parameter is useful only if you request results at 4 or more frequency points. It is used to bias the results points toward the ends of the intervals so that better resolution is obtained there. This option is recommended if you have toggled on Use eigenfrequencies to subdivide each frequency range, since the ends of each interval are the eigenfrequencies where the response amplitudes vary most rapidly.

For more information, see “The bias parameter” in “Direct-solution steady-state dynamic analysis,” Section 6.3.4 of the ABAQUS Analysis User's Manual.

For detailed information on how to enter data, see “Entering tabular data,” Section 3.2.7.

To configure settings on the Other tabbed page:

In the Edit Step dialog box, display the Other tabbed page.

(For information on displaying the Edit Step dialog box, see “Creating a step,” Section 14.9.2, or “Editing a step,” Section 14.9.3.)

Select the Matrix storage option of your choice:

Select Use solver default to allow ABAQUS/Standard to decide whether a symmetric or unsymmetric matrix storage and solution scheme is needed.

Select Unsymmetric to restrict ABAQUS/Standard to the unsymmetric storage and solution scheme.

Select Symmetric to restrict ABAQUS/Standard to the symmetric storage and solution scheme.

For more information on matrix storage, see “Matrix storage and solution scheme in ABAQUS/Standard” in “Procedures: overview,” Section 6.1.1 of the ABAQUS Analysis User's Manual.