Fix - support pow(x,n) function in formula

Author: linev

changes.md

@@ -1,5 +1,9 @@
 # JSROOT changelog
 
+## Changes in 5.2.x
+1. Fix - support pow(x,n) function in formula
+
+
 ## Changes in 5.2.3
 1. Fix - potential mix-up in marker attributes handling
 2. Fix - unzomming of log scale https://root-forum.cern.ch/t/25889

scripts/JSRootCore.js

@@ -1609,6 +1609,7 @@
                            .replace(/\b(cos)\b/gi, 'Math.cos')
                            .replace(/\b(tan)\b/gi, 'Math.tan')
                            .replace(/\b(exp)\b/gi, 'Math.exp')
+                           .replace(/\b(pow)\b/gi, 'Math.pow')
                            .replace(/pi/g, 'Math.PI');
               for (var n=2;n<10;++n)
                  _func = _func.replace('x^'+n, 'Math.pow(x,'+n+')');