[BangPypers] File read
steve
steve at lonetwin.net
Mon Nov 7 18:26:52 CET 2011
Hey Shashidhar,
Others may answer your question, I am not going to do that right away. I'll just
offer a few suggestions to clean up your code. If you do that, I promise to
answer your questions:
a. Use os.path.join() to join path components
b. You don't /have/ to read all the lines of the file into a list before
processing it. The pythonic way would be:
with open(filename) as input_file:
for line in input_file.readline():
...do stuff ...
c. You don't need to iterate over lists using numeric indexes. Even if you
/need/ numeric index, use enumerate. So, instead of :
for index in range(len(somelist)):
...do something with somelist[index] ...
OR
...do something with index ...
use something like:
for element in somelist:
...do something with element...
OR
for index, element in enumerate(somelist):
...do something with index or element ....
d. Don't chain string operations to just match a substring, use regular
expressions. If you /have/ to chain string operations (for instance, to extract
rather than match), chain them only once. So, instead of :
if all_lines_in_file[line].split('->')[1].split(')')[0].split("'")[1].strip() ==
"true":
...
...
print "ZMP value %s" %
all_lines_in_file[line].split('->')[1].split(')')[0].split("'")[1].strip()
...and more such monstrosities, do either:
stuff_that_interests_me = line.split('->')[1].split(')')[0]("'")[1].strip()
if stuff_that_interests_me == 'true':
....
or just:
matched = re.search("->\((.*)\)", line) # or some such, depending on the format
if matched:
stuff_that_interests_me = matched.group()
....
e. If you need one of three options as values of a dict (which I assume will
serve as a config dict), default the config keys to something. So, do:
config = {'MyFirstKey' : 'ASK',
'MyNextKey' : 'ASK',
...
}
for line in all_lines:
...extract stuff_that_interests_me from line...
if 'MyFirstKey' in line:
if stuff_that_interests_me == 'true':
config['MyFirstKey'] = 'ON'
elif stuff_that_interests_me == 'false':
config['MyFirstKey'] = 'OFF'
...
HTH,
cheers,
- steve
On 11/07/2011 05:17 PM, Shashidhar Paragonda wrote:
> Dear Python hackers,
>
> I have text file. I read each line and store it in List.
>
> my requirement is I need to check only 6 special lines from i.e
>
> 1. resultToPDFFile
> 2. resultToPDFFileDialog
> 3. resultToQdasFile
> 4. resultToQdasFileDialog
> 5. resultToTableFile
> 6. resultToTableFileDialog
>
> Note: each line have value set in the end eg: "resultToPDFFile '->' true"
>
> my conditions are:
> if first line mentioned above found check the value if it "true"
> set dictionary item D['PDF'] = "ON"
> else if value is not "true" then
> check for line resultToPDFFileDialog if value is "off"
> set dictionary item D['PDF'] = "OFF"
> else:
> set dictionary item D['PDF'] = "ASK"
>
> for example these are the lines in file:
>
> resultToPDFFile '->' 'true'
>
> resultToPDFFileDialog '->' 'on'
>
> >> I have put if else condition statements exactly same as I mentioned
> above.
> >> now my problem is though the resultToPDFFile is "true"
> >> first time I get the value as ON for dictionary item D['PDF']
> >> When loop starts for finding other lines i.e numbers 3& 4 from
> above list my Dictionary item D['PDF'] is becoming "ASK"
> >> the loop is entering into last else part.
> >> what is problem I am not gotting
> >> is my if else structure is wrong or not I am totally not getting
> other idea please help
> >> thank you in advance.
>
> the code is:
>
>>>>
>
> inspset_file_pointer = open("%s/%s" % (self.inspsetfile_path,
> self.inspection_file), "r")
> # Read all lines from the INSPSET file from the TEMPORARY
> directory path
> all_lines_in_file = inspset_file_pointer.readlines()
> inspset_file_pointer.close()
> # loop through all the lines from the file
> print "readlines from the file"
> for line in range(0, len(all_lines_in_file)-1):
> time.sleep(.5)
> if "measPointsForLaterEval" in all_lines_in_file[line]:
> print "ZMP line found %s" % all_lines_in_file[line]
> if
> all_lines_in_file[line].split('->')[1].split(')')[0].split("'")[1].strip()
> == "true":
> time.sleep(.3)
> print all_lines_in_file[line]
> print "ZMP value %s" %
> all_lines_in_file[line].split('->')[1].split(')')[0].split("'")[1].strip()
> self.cnc_parameters['ZMP'] = "ON"
> print "dictionary values in ZMP %s" %
> self.cnc_parameters
> exit
> elif "measPointsForLaterEvalDialog" in
> all_lines_in_file[line]:
> if
> all_lines_in_file[line+1].split(')')[0].split('#')[1] == "off":
> time.sleep(.3)
> print all_lines_in_file[line]
> print "ZMP dialog value %s" %
> all_lines_in_file[line+1].split(')')[0].split('#')[1]
> self.cnc_parameters['ZMP'] = "OFF"
> print "dictionary values in ZMP %s" %
> self.cnc_parameters
> exit
> else:
> self.cnc_parameters['ZMP'] = "ASK"
>
> elif "resultsToPDFFile" in all_lines_in_file[line]:
> print "PDF line found %s" % all_lines_in_file[line]
> # check if current line i.e resultToPDFFile line has
> value is 'true'
> # same verification lines are same for rest of the
> keywords
> if
> all_lines_in_file[line].split('->')[1].split(')')[0].split("'")[1].strip()
> == "true":
> time.sleep(.3)
> print all_lines_in_file[line]
> print "PDF value %s" %
> all_lines_in_file[line].split('->')[1].split(')')[0].split("'")[1].strip()
> self.cnc_parameters['PDF'] = "ON"
> print "dictionary values in PDF %s" %
> self.cnc_parameters
> elif "resultToExportToPDFDialog" in
> all_lines_in_file[line]:
> if
> all_lines_in_file[line+1].split(')')[0].split('#')[1] == "off":
> time.sleep(.3)
> print all_lines_in_file[line]
> print "PDF dialog value %s" %
> all_lines_in_file[line+1].split(')')[0].split('#')[1]
> self.cnc_parameters['PDF'] = "OFF"
> print "dictionary values in PDF %s" %
> self.cnc_parameters
> else:
> self.cnc_parameters['PDF'] = "ASK"
>
> elif "resultToQdasFile" in all_lines_in_file[line]:
> print "Qdas line found %s" % all_lines_in_file[line]
> if
> all_lines_in_file[line].split('->')[1].split(')')[0].split("'")[1].strip()
> == "true":
> time.sleep(.3)
> print all_lines_in_file[line]
> print "QDAS value %s" %
> all_lines_in_file[line].split('->')[1].split(')')[0].split("'")[1].strip()
> self.cnc_parameters['QDAS'] = "ON"
> print "dictionary values in QDAS %s" %
> self.cnc_parameters
> exit
> elif "resultToQdasFileDialog" in
> all_lines_in_file[line]:
> if
> all_lines_in_file[line+1].split(')')[0].split('#')[1] == "off":
> time.sleep(.3)
> print all_lines_in_file[line]
> print "QDAS dialog value %s" %
> all_lines_in_file[line+1].split(')')[0].split('#')[1]
> self.cnc_parameters['QDAS'] = "OFF"
> print "dictionary values in QDAS %s" %
> self.cnc_parameters
> exit
> else:
> self.cnc_parameters['QDAS'] = "ASK"
>
> elif "resultToTableFile" in all_lines_in_file[line]:
> print "HDR line found %s" % all_lines_in_file[line]
> if
> all_lines_in_file[line].split('->')[1].split(')')[0].split("'")[1].strip()
> == "true":
> time.sleep(.3)
> print all_lines_in_file[line]
> print "HDR value %s" %
> all_lines_in_file[line].split('->')[1].split(')')[0].split("'")[1].strip()
> self.cnc_parameters['HDR'] = "ON"
> print "dictionary values in HDR %s" %
> self.cnc_parameters
> exit
> elif "resultToTableFileDialog" in
> all_lines_in_file[line]:
> if
> all_lines_in_file[line+1].split(')')[0].split('#')[1] == "off":
> time.sleep(.3)
> print all_lines_in_file[line]
> print "HDR dialog value %s" %
> all_lines_in_file[line+1].split(')')[0].split('#')[1]
> self.cnc_parameters['HDR'] = "OFF"
> print "dictionary values in HDR %s" %
> self.cnc_parameters
> exit
> else:
> self.cnc_parameters['HDR'] = "ASK"
>
--
random spiel: http://lonetwin.net/
what i'm stumbling into: http://lonetwin.stumbleupon.com/
More information about the BangPypers
mailing list