I have a CSV file where fields are delimited with a comma. The fields of this CSV file contains the attributes of Permanent Survey Marks and I’ve created a GIS python script to convert it to a table that is stored it in our Enterprise GIS Spatial Database (SQL Server).
Within each row, there are some field’s that contain whitespace only. For example, part of a typical line shown here:
, ,N,NRM ,SP109773 , ,CK3693 , ,CK3543 ,
I discovered that these whitespace fields were being stored in the table as a string of whitespace characters. I needed to determine if each field had whitespace characters only and then make the script store these particular fields with a null value in the table. I came up with this function to do the job:
def isWhiteSpaceString(string):
""" Check if string only contains whitespace characters.
Input: string value
Output: Returns True if string contains only whitespace
characters otherwise returns False
"""
if (str == None):
return False
flag = 0
for char in string:
if char == " ":
continue
else:
flag = 1
break
if flag == 0:
# string only contains whitespace characters
return True
else:
# string contains as least one alphanumeric character
return False
# ---------------------------------------------------------------------------- #
a = 'abcdefg12345'
b = 'abcdefg12345 '
c = ' abcdefg12345'
d = '! '
e = ' '
print isWhiteSpaceString(a)
print isWhiteSpaceString(b)
print isWhiteSpaceString(c)
print isWhiteSpaceString(d)
print isWhiteSpaceString(e)*** Python 2.5.1 (r251:54863, Apr 18 2007, 08:51:08) [MSC v.1310 32 bit (Intel)] on win32. ***
>>>
False
False
False
False
True
>>>
This works but I’m looking for alternative solution that might be a little more compact or even more efficient.