# CHEBY

The Cheby function evaluates a Chebyshev polynomial at a specific value $x$ .

## Format

$\text{Cheby}\left(x,{x}_{0},{c}_{0},{c}_{1},\cdots ,{c}_{30}\right)$

## Arguments

$x$
The independent variable. For example, to specify time as the independent variable, specify $x$ as TIME.
${x}_{0}$
The phase shift in the Chebychev polynomial.
${c}_{0},{c}_{1},\cdots ,{c}_{30}$
The coefficients in the Chebychev polynomial. Specify only as many coefficients as needed with a maximum of 31 coefficients.

(1)

## Example

<Force_Vector_TwoBody
id                    = "30101"
type                  = "ForceOnly"
i_marker_id           = "30102031"
j_floating_marker_id  = "30101031"
ref_marker_id         = "30101010"
fx_expression         = BISTOP(DX(30102030,30101010,30101010),
VX(30102030,30101010,30101010),0.5,9.5,10000000,2.1,1,0.001)"
fy_expression         = "0"
fz_expression         = "0"
/>