Specifies the approximate number of significant figures in the calculated eigenvalues (w2, where w is the angular frequency in rad/sec). The default value is 6. For example, if a calculated eigenvalue is 44032.32383 using the default value of 6, then the first digit to the right of the decimal is usually the last accurately computed figure.
The eigenvectors, or mode shapes, are calculated to half as many significant figures as are the eigenvalues. If the eigenvalues have six significant figures of accuracy, then the eigenvectors have three.
This number should not be decreased. Increases to 8 or 10 are not unusual but result in slower solutions with little change in response results.