1 files changed, 2 insertions, 2 deletions
diff --git a/sh/il b/sh/il
index 7c75a71..7741695 100755
--- a/sh/il
+++ b/sh/il
@@ -1,6 +1,6 @@
 #!/bin/sh
 # InterpoLation
 
-# x=$1, xa=$2, xb=$3, ya=$4, yb=$5
+# y=?, x=$1, xa=$2, xb=$3, ya=$4, yb=$5, scale=$6
 # https://en.wikipedia.org/wiki/Interpolation#Linear_interpolation
-echo "scale=4;$4+($5-$4)*($1-$2)/($3-$2)" | bc
+echo "scale=${6:-4};$4+($5-$4)*($1-$2)/($3-$2)" | bc