# Create an M-spline survival model, both structure and parameters.

Source:`R/mspline_init.R`

`msplinemodel_init.Rd`

`mspline_init`

is first used to create the M-spline
model structure, including knot positions. Parameters including
basis coefficients and scale are either supplied or set to a
default that defines a constant hazard model.

## Usage

```
msplinemodel_init(
df = 10,
degree = 3,
bsmooth = TRUE,
knots = NULL,
bknot = 10,
obstimes = NULL,
coefs = NULL,
hscale = 1
)
```

## Arguments

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

`bsmooth`

is`FALSE`

.- bsmooth
If

`TRUE`

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

- obstimes
Vector of observation times whose quantiles will be used to choose knot locations

- coefs
Basis coefficients

- hscale
Hazard scale parameter

## Value

A list defining the M-spline, with any omitted list
components set to defaults. See `mspline_init`

for
details. The parameters are included as the `coefs`

and
`hscale`

components.