diff --git a/uniplot.ss b/uniplot.ss
index 95476d0..53ed9eb 100755
--- a/uniplot.ss
+++ b/uniplot.ss
@@ -3,15 +3,18 @@
 (export main)
 
 (import :std/iter
+	:std/misc/func
 	:std/text/csv
 	:dlozeve/uniplot/lineplot)
 
+(def (parse-number s)
+  (or (string->number s) +nan.0))
+
 (def (main . args)
   (def csv (read-csv-lines (current-input-port)))
   (def names (car csv))
   (def lsts
-    (apply map list
-	   (for/collect ((row (cdr csv)))
-	     (for/collect ((x row))
-	       (or (string->number x) +nan.0)))))
+    (for/fold (lsts (repeat '() (length names)))
+	((row (cdr csv)))
+      (map cons (map parse-number row) lsts)))
   (displayln (line-plot lsts title: (if (null? args) "" (car args)) names: names)))
diff --git a/uniplot/lineplot.ss b/uniplot/lineplot.ss
index b5fec98..291683b 100644
--- a/uniplot/lineplot.ss
+++ b/uniplot/lineplot.ss
@@ -76,18 +76,18 @@
     (match lsts
       ([ys] (let ((xmin 0)
 		  (xmax (length ys))
-		  (ymin (apply nanmin ys))
-		  (ymax (apply nanmax ys)))
+		  (ymin (for/fold (ymin +nan.0) (y ys) (nanmin ymin y)))
+		  (ymax (for/fold (ymax +nan.0) (y ys) (nanmax ymax y))))
 	      (values xmin xmax ymin ymax
 		      [(draw-canvas (iota (length ys)) ys
 				    (scale-fn xmin xmax)
 				    (scale-fn ymin ymax)
 				    width: width height: height)])))
-      ([xs . yss] (let* ((xmin (apply nanmin xs))
-			 (xmax (apply nanmax xs))
+      ([xs . yss] (let* ((xmin (for/fold (xmin +nan.0) (x xs) (nanmin xmin x)))
+			 (xmax (for/fold (xmax +nan.0) (x xs) (nanmax xmax x)))
 			 (all-ys (flatten yss))
-			 (ymin (apply nanmin all-ys))
-			 (ymax (apply nanmax all-ys))
+			 (ymin (for/fold (ymin +nan.0) (y all-ys) (nanmin ymin y)))
+			 (ymax (for/fold (ymax +nan.0) (y all-ys) (nanmax ymax y)))
 			 (x-scale-fn (scale-fn xmin xmax))
 			 (y-scale-fn (scale-fn ymin ymax)))
 		    (values xmin xmax ymin ymax