我初学ansys-dyna，再做实例过程中，老是出现这么一个warning
The labels AX, AY, AZ, VX, VY,VZ are not allowed in the D command for
Explicit Dynamics Applications. Some of these constraints were
specified but will not be used in the solution. Try using the EDLOAD
command instead.
大体意思是什么
什么是D command ，EDLOAD command
望不吝赐教
