Apply maintainer suggestion: use toFixed instead of string manipulation

Author: Hasnaathussain

src/plots/cartesian/axes.js

@@ -2210,27 +2210,7 @@ function numFormat(v, ax, fmtoverride, hover) {
             v = v.slice(0, Math.max(0, v.length + tickRound));
             for(var i = tickRound; i < 0; i++) v += '0';
         } else {
-            var vStr = String(v);
-            var ep = vStr.indexOf('e');
-            if(ep >= 0) {
-                var mantissa = vStr.slice(0, ep);
-                var exponentStr = vStr.slice(ep);
-                var dp = mantissa.indexOf('.') + 1;
-                var exponentVal = parseInt(exponentStr.slice(1), 10);
-                var adjustedTickRound = tickRound + exponentVal;
-                if(dp) {
-                    if(adjustedTickRound < 0) {
-                        mantissa = mantissa.slice(0, dp - 1);
-                    } else {
-                        mantissa = mantissa.slice(0, dp + adjustedTickRound).replace(/\.?0+$/, '');
-                    }
-                }
-                v = mantissa + exponentStr;
-            } else {
-                v = vStr;
-                var dp = v.indexOf('.') + 1;
-                if(dp) v = v.slice(0, dp + tickRound).replace(/\.?0+$/, '');
-            }
+            v = v.toFixed(Math.max(0, Math.min(20, tickRound))).replace(/\.?0+$/, '');
         }
         // insert appropriate decimal point and thousands separator
         v = Lib.numSeparate(v, ax._separators, separatethousands);