fix checks & update vignette
diff --git a/man/spec_angle.Rd b/man/spec_angle.Rd
index 6bef9bb..5df2b13 100644
--- a/man/spec_angle.Rd
+++ b/man/spec_angle.Rd
@@ -4,7 +4,7 @@
 \alias{spec_angle}
 \title{Generate rotation angle for continuous values}
 \usage{
-spec_angle(x)
+spec_angle(x, begin, end)
 }
 \arguments{
 \item{x}{continuous vectors of values}