昨天，寫了一個將羅馬數字轉換成阿拉伯數字的過程，今天來寫一個反過程吧，將阿拉伯數字轉化成羅馬字串
實現原理很簡單，一看就能明白的，將數字先拆分成一個一個的小於10的數字，然後在各自轉換則可。

def numToRomanNum(Num):
 """digital will be converted into Roman numerals,Ex: numToRomanNum(3999)"""
     if Num < 1 or Num > 3999:
         print 'The Num must in 1-3999'
     else
 
:
         NumDic = {
             '1':('I','IV','V','IX'),
             '2':('X','XL','L','XC'),
             '3':('C','CD','D','CM'),
             '4':('M')
             }
         items = sorted(NumDic.items())
         retstr = ''
         for item in items:
             str = ''
             (Num,modNum) = divmod(Num,10)
             if
 
 modNum != 0:
                 if item[0] != '4':
                     if modNum <= 3:
                         while modNum > 0:
                             str = str.join(['',item[1][0]])
                             modNum -= 1
                     elif modNum < 5:
                         str = item[1][1]
                     elif
 
 modNum == 5:
                         str = item[1][2]
                     elif modNum < 9:
                         str = item[1][2]
                         while modNum > 5:
                             str = str.join(['',item[1][0]])
                             modNum -= 1
                     else:
                         str = item[1][3]
                 else:
                     while modNum > 0:
                         str = str.join(['',item[1][0]])
                         modNum -= 1
                 retstr = str.join(['',retstr])
         return retstr