1 files changed, 6 insertions, 7 deletions
diff --git a/R/drfit.R b/R/drfit.R
index c3fc945..a3b8a1b 100644
--- a/R/drfit.R
+++ b/R/drfit.R
@@ -23,13 +23,12 @@ drdata <- function(substances, experimentator = "%", db = "cytotox",
 drfit <- function(data, startlogEC50 = NA, lognorm = TRUE, logis = FALSE,
         linearlogis = FALSE, b0 = 2, f0 = 0)
 {
-    library(nls)
-        substances <- levels(data$substance)
-        unit <- levels(as.factor(data$unit))
-        logisf <- function(x,x0,b,k=1)
-        {
-            k / (1 + (x/x0)^b)
-        }
+    substances <- levels(data$substance)
+    unit <- levels(as.factor(data$unit))
+    logisf <- function(x,x0,b,k=1)
+    {
+        k / (1 + (x/x0)^b)
+    }
     linearlogisf <- function(x,k,f,mu,b)
     {
         k*(1 + f*x) / (1 + ((2*f*(10^mu) + 1) * ((x/(10^mu))^b)))