# Get basis for an illustration of an M-spline with given knots.

Source:`R/mspline_plots.R`

`mspline_plotsetup.Rd`

Get basis for an illustration of an M-spline with given knots.

## Usage

```
mspline_plotsetup(
knots,
bknot = 10,
tmin = NULL,
tmax = NULL,
degree = 3,
df = 10,
bsmooth = TRUE
)
```

## Arguments

- knots
Vector of knot locations. If not supplied,

`df`

has to be specified. One of two rules is then used to choose the knot locations. If`bknot`

is specified, a set of equally spaced knots between zero and`bknot`

is used. Otherwise if`obstimes`

is supplied, the knots are chosen as equally spaced quantiles of`obstimes`

.The number of knots (excluding zero) is

`df - degree + 1`

if`bsmooth`

is`TRUE`

, or`df - degree - 1`

otherwise.- bknot
Location of the final spline knot.

- tmin
Minimum plotting time. Defaults to zero.

- tmax
Maximum plotting time. Defaults to the highest knot.

- degree
Spline polynomial degree. Can only be changed from the default of 3 if

`bsmooth`

is`FALSE`

.- df
Desired number of basis terms, or "degrees of freedom" in the spline. If

`knots`

is not supplied, the number of knots is then chosen to satisfy this.- bsmooth
If

`TRUE`

then the function is constrained to also have zero derivative and second derivative at the boundary.

## Value

Data frame containing the basis, as returned by `mspline_basis`

.