Mapdl.dsum(signif='', label='', td='', forcetype='', **kwargs)

Specifies the double sum mode combination method.

APDL Command: DSUM


Combine only those modes whose significance level exceeds the SIGNIF threshold. For single point, multipoint, or DDAM response (SPOPT, SPRS, MPRS, or DDAM), the significance level of a mode is defined as the mode coefficient of the mode, divided by the maximum mode coefficient of all modes. Any mode whose significance level is less than SIGNIF is considered insignificant and is not contributed to the mode combinations. The higher the SIGNIF threshold, the fewer the number of modes combined. SIGNIF defaults to 0.001. If SIGNIF is specified as 0.0, it is taken as 0.0. (This mode combination method is not valid for SPOPT, PSD.)


Label identifying the combined mode solution output.

DISP - Displacement solution (default). Displacements, stresses, forces, etc., are


VELO - Velocity solution. Velocities, “stress velocities,” “force velocities,” etc.,

are available.

ACEL - Acceleration solution. Accelerations, “stress accelerations,” “force

accelerations,” etc., are available.


Time duration for earthquake or shock spectrum. TD defaults to 10.


Label identifying the forces to be combined:

STATIC - Combine the modal static forces (default).

TOTAL - Combine the modal static plus inertial forces.


This command is also valid for PREP7.