# WDTM

The WDTM function computes the magnitude of the total relative
rotational acceleration between markers `I` and `J`.
Time derivatives are calculated in the reference frame of marker `L`.
The first argument, marker `I`, must be specified.

## Format

WDTM(I, J, L)## Arguments

`I`- The marker whose acceleration is to be computed.
`J`- The marker with respect to which the acceleration is to be computed. If omitted, it defaults to the ground coordinate system.
`L`- Time derivatives are taken in the coordinate system of this marker. If omitted, it defaults to the ground coordinate system.

## Example

```
<Post_Request
comment = "WM-WDTM-HAVSIN-FORSIN-DIM-ACOS"
id = "3"
type = "EXPRESSION"
expr1 = "NULL"
expr2 = "WM(30102010)"
expr3 = "WDTM(30102010)"
expr4 = "HAVSIN(TIME,1.,0.,4.,1.)"
expr5 = "NULL"
expr6 = "FORSIN(TIME,0.1,6.28,0.1,0.2)"
expr7 = "DIM(TIME,1.0)"
expr8 = "ACOS(COS(TIME))"
/>
```