fix test issue

Author: actuaryzhang

R/pkg/NAMESPACE

@@ -402,8 +402,6 @@ export("partitionBy",
 export("windowPartitionBy",
        "windowOrderBy")
 
-export("tweedie")
-
 S3method(print, jobj)
 S3method(print, structField)
 S3method(print, structType)

R/pkg/R/mllib_regression.R

@@ -47,8 +47,8 @@ setClass("IsotonicRegressionModel", representation(jobj = "jobj"))
 #' @return a list for internal use in spark.glm
 tweedie <- function(var.power = 0.0, link.power = 1.0 - var.power) {
   list(family = "tweedie",
-       variance = function (mu) mu^var.power,
-       linkfun = function (mu) mu^link.power,
+       variance = function(mu) mu ^ var.power,
+       linkfun = function(mu) mu ^ link.power,
        link = paste("mu^", as.character(link.power), sep = ""))
 }