# FX

The FX function computes the X-component of the resultant translational force acting at marker I (obtained by vector summation), due to all applied forces and constraints that act between markers I and J, as resolved in the coordinate system of marker K.

FX(I, J, K)

## Description

If the J marker is not specified, then FX computes the X-component of all the resultant forces at marker I. The first argument, marker I, must be specified. The second and third arguments, markers J and K, are optional.

## Arguments

I
The marker at which the resultant force is to be computed.
J
The second marker such that all forces between markers I and J are to be summed up at the marker I location.
K
The resultant force vector is resolved in the coordinate system of the K marker. This argument is optional. If omitted, it defaults to the ground coordinate system. To specify a K marker without specifying a J marker, set the J marker to zero.

## Example

<Post_Request
comment             = "bush-frc"
id                  = "70000045"
type                = "EXPRESSION"
expr1               = "NULL"
expr2               = "FX(30301010,30301011,30301011)"
expr3               = "FY(30301010,30301011,30301011)"
expr4               = "FZ(30301010,30301011,30301011)"
expr5               = "NULL"
expr6               = "TX(30301010,30301011,30301011)"
expr7               = "TY(30301010,30301011,30301011)"
expr8               = "TZ(30301010,30301011,30301011)"
/>