Converts an Excel-style column name to a number. (JavaScript / Python)

colNameToNum.js

//
// Convert an Excel-style column name to a number.
//
// Code: Hiroshi Yamamoto

function colNameToNum(name) {
  var colNum = 0;
  var pow = 1;
  var i = name.length;
  while(i--) {
    var letter = name[i];
    colNum += (letter.charCodeAt(0) - 64) * pow;
    pow *= 26;
  }
  return colNum;
}

colNameToNum.py

#
# Convert an Excel-style column name to a number.
#
# Code: Chris West (http://cwestblog.com/2013/09/13/python-convert-excel-column-name-to-number/)

def colNameToNum(name):
    pow = 1
    colNum = 0
    for letter in name[::-1]:
            colNum += (int(letter, 36) -9) * pow
            pow *= 26
    return colNum