# Mean and restricted mean survival functions

Source:`R/Exp.R`

, `R/Gamma.R`

, `R/GenF.R`

, and 7 more
`means.Rd`

Mean and restricted mean survival time functions for distributions which are built into flexsurv.

## Usage

```
mean_exp(rate = 1)
rmst_exp(t, rate = 1, start = 0)
mean_gamma(shape, rate = 1)
rmst_gamma(t, shape, rate = 1, start = 0)
rmst_genf(t, mu, sigma, Q, P, start = 0)
mean_genf(mu, sigma, Q, P)
rmst_genf.orig(t, mu, sigma, s1, s2, start = 0)
mean_genf.orig(mu, sigma, s1, s2)
rmst_gengamma(t, mu = 0, sigma = 1, Q, start = 0)
mean_gengamma(mu = 0, sigma = 1, Q)
rmst_gengamma.orig(t, shape, scale = 1, k, start = 0)
mean_gengamma.orig(shape, scale = 1, k)
rmst_gompertz(t, shape, rate = 1, start = 0)
mean_gompertz(shape, rate = 1)
mean_llogis(shape = 1, scale = 1)
rmst_llogis(t, shape = 1, scale = 1, start = 0)
mean_lnorm(meanlog = 0, sdlog = 1)
rmst_lnorm(t, meanlog = 0, sdlog = 1, start = 0)
mean_weibull(shape, scale = 1)
rmst_weibull(t, shape, scale = 1, start = 0)
rmst_weibullPH(t, shape, scale = 1, start = 0)
mean_weibullPH(shape, scale = 1)
```

## Arguments

- rate
Rate parameter (exponential and gamma)

- t
Vector of times to which restricted mean survival time is evaluated

- start
Optional left-truncation time or times. The returned restricted mean survival will be conditioned on survival up to this time.

- shape
Shape parameter (Weibull, gamma, log-logistic, generalized gamma [orig], generalized F [orig])

- mu
Mean on the log scale (generalized gamma, generalized F)

- sigma
Standard deviation on the log scale (generalized gamma, generalized F)

- Q
Vector of first shape parameters (generalized gamma, generalized F)

- P
Vector of second shape parameters (generalized F)

- s1
Vector of first F shape parameters (generalized F [orig])

- s2
vector of second F shape parameters (generalized F [orig])

- scale
Scale parameter (Weibull, log-logistic, generalized gamma [orig], generalized F [orig])

- k
vector of shape parameters (generalized gamma [orig]).

- meanlog
Mean on the log scale (log normal)

- sdlog
Standard deviation on the log scale (log normal)

## Value

mean survival (functions beginning 'mean') or restricted mean survival (functions beginning 'rmst_').