diff --git a/more_math/Parser/MathExpr.g4 b/more_math/Parser/MathExpr.g4
index ca871af..32a1896 100644
--- a/more_math/Parser/MathExpr.g4
+++ b/more_math/Parser/MathExpr.g4
@@ -339,7 +339,7 @@ COLON: ':';
 LBRACE: '{';
 RBRACE: '}';
 
-NUMBER: ([0-9]+('.'[0-9]*)? | '.'[0-9]+)([eE][+-]?[0-9]+)?;
+NUMBER: ([0-9]+ ('.' [0-9]*)? | '.' [0-9]+) ([eE][+-]? [0-9]+)?;
 CONSTANT: ('pi' | 'PI' | 'e' | 'E');
 VARIABLE: [a-zA-Z_] [a-zA-Z_0-9]*;