c2a {smoothSurv} | R Documentation |
Work Function for 'smoothSurvReg'
Description
Compute the 'a' G-spline coefficients from 'c' G-spline coefficients.
Usage
c2a(ccoef, which.zero = which.max(ccoef), toler = 1e-6)
Arguments
ccoef |
A vector of 'c' G-spline coefficients. |
which.zero |
An index of the 'a' G-spline coefficient which will be zero (the reference one). |
toler |
All 'c' coefficients smaller in absolute value than |
Details
'c' and 'a' G-spline coefficients are related by the expression
c_j = \frac{\exp(a_j)}{\sum_{l=1}^{g}\exp(a_l)}, j = 1,\dots, g,
where a_k = 0,
k = which.zero
.
This function transforms the 'c' coefficients into their 'a' counterparts.
Value
A vector of same length as ccoef
with 'a' G-spline coefficients.
Author(s)
Arnošt Komárek arnost.komarek@mff.cuni.cz
See Also
Examples
ccoef <- c(0.1, 0.2, 0.15, 0.3, 0.25)
### Compute 'a' counterparts
acoef <- c2a(ccoef, 1)
print(acoef)
### And back 'c', ccoef2 should be same as ccoef
ccoef2 <- a2c(acoef)
print(ccoef2)
[Package smoothSurv version 2.6 Index]