diff --git a/src/main/java/org/apache/commons/math/util/FastMath.java b/src/main/java/org/apache/commons/math/util/FastMath.java
index 6f1cc9f10..0df119490 100644
--- a/src/main/java/org/apache/commons/math/util/FastMath.java
+++ b/src/main/java/org/apache/commons/math/util/FastMath.java
@@ -3270,11 +3270,25 @@ public class FastMath {
      * @param x number from which ulp is requested
      * @return ulp(x)
      */
-
     public static double ulp(double x) {
+        if (Double.isInfinite(x)) {
+            return Double.POSITIVE_INFINITY;
+        }
         return abs(x - Double.longBitsToDouble(Double.doubleToLongBits(x) ^ 1));
     }
 
+    /**
+     * Compute least significant bit (Unit in Last Position) for a number.
+     * @param x number from which ulp is requested
+     * @return ulp(x)
+     */
+    public static float ulp(float x) {
+        if (Float.isInfinite(x)) {
+            return Float.POSITIVE_INFINITY;
+        }
+        return abs(x - Float.intBitsToFloat(Float.floatToIntBits(x) ^ 1));
+    }
+
     /**
      * Get the next machine representable number after a number, moving
      * in the direction of another number.