diff --git a/cal4.java b/cal4.java
new file mode 100644
index 0000000..81abca3
--- /dev/null
+++ b/cal4.java
@@ -0,0 +1,9 @@
+package opencv;
+
+import java.util.*;;
+
+public class Log {
+	public static double log(double a) {
+		return Math.log(a);
+		}
+}
\ No newline at end of file