>>  realstring='www.wanbao.com http://www.gov.cn '
realstring =
www.wanbao.com http://www.gov.cn 
>>  A=isspace(realstring)
A =
  Columns 1 through 11 
     0     0     0     0     0     0     1     0     0     0     0
  Columns 12 through 22 
     0     0     0     1     0     0     0     0     1     0     0
  Columns 23 through 33 
     0     0     0     1     0     0     0     0     0     0     0
  Columns 34 through 37 
     1     0     0     0
>> B=isletter(realstring)
B =
  Columns 1 through 11 
     1     0     1     0     1     0     1     0     1     1     0
  Columns 12 through 22 
     1     0     1     0     1     1     0     0     0     0     0
  Columns 23 through 33 
     1     1     1     0     1     1     1     0     1     1     1
  Columns 34 through 37 
     0     1     0     0
>>
