add laplace function

1 files changed, 10 insertions, 0 deletions

diff --git a/R/priors.R b/R/priors.R
index 81e5560..9313d0d 100644
--- a/R/priors.R
+++ b/R/priors.R
@@ -88,6 +88,16 @@ gamma <- function(shape=1, rate=1){
   list(dist=5, par1=shape, par2=rate, par3=0, autoscale=FALSE)
 }
 
+#' @rdname priors
+#' @export
+laplace <- function(location=0, scale=2.5, autoscale=TRUE){
+  stopifnot(all(scale > 0))
+  if((length(location) > 1) & (length(scale) > 1)){
+    stopifnot(length(location) == length(scale))
+  }
+  list(dist=6, par1=location, par2=scale, par3=0, autoscale=autoscale)
+}
+
 null_prior <- function(){
   list(dist=0, par1=0, par2=0, par3=0, autoscale=FALSE)
 }