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Printing words with the same first and last character and words with the same second character and one before the last character

#!/ usr/bin/python3
import sys
def main():
for line in sys.stdin:
line = line.split()
x = -1
for word in line:
if word[-1]==word[0] or word[x-1]==word[1]:
print(word)
main()
It also prints dots at the end of the sentences, why?
And words like 'cat' and 'moon' should also be out of the question. But it also prints these words.
Can someone point me in the right direction please?

I think your problem is because the second and second last characters of 'cat' are the same.
def main():
for line in sys.stdin:
line = line.split()
x = -1
for word in line:
if (word[-1]==word[0] and len(word)<=2) or (word[x-1]==word[1] and len(word)<=4):
print(word)
or something like that, depending on your preference.

This should get rid of that pesky cat, although moon stays.
It will also include words that use upper and lower case characters, so sadly not only will moon print but also Moon, MOon, mooN and moOn.
Edit: Forgot to test for one character words (a, I etc)
import sys
def main():
for line in sys.stdin:
line = line.split()
for word in line:
uword = word.lower()
if len(uword) > 1:
if uword[0:1]==uword[-1] or (uword[1:2]==uword[-2] and len(uword) > 3):
print(word)
main()

I got it guys, understood the question wrong. This prints the right words, that I got beforehand. That cleared things up for me. This is the right code but it still gives "sys.excepthook is missing". I run this code with another code that gives a space an newline. So every space between words becomes a newline:
cat cdb.sentences| python3 newline.py| python3 word.py |head -n 5
import sys
def main():
for line in sys.stdin:
line = line.split()
for word in line:
letterword = lw = word.lower()
if len(lw) > 1:
if lw[0:1]==lw[-1] and (lw[1:2]==lw[-2]):
print(word)
main()
import sys
def main():
for line in sys.stdin:
line = line.rstrip()
text = ""
for word in line:
if word in ' ':
text=text + '\n'
else:
text=text + word
print(text)
main()
It should give the 5 first words that have the same first, last letter, -2 and 1 letters. With an white line between each one of them. First i want to solve that hook.
Thx

You are not helping yourself by answering your own question with what is essentially a completely different question in an answer.
You should have closed your original off by accepting one of the answers, if one of them helped, which it looked like they did and then asked a new question.
However, the answer to your 2nd question/answer can be found here:
http://python.developermemo.com/7757_12807216/ and it is a brilliant answer
Synopsis:
The reason this is happening is that you're piping a nonzero amount of output from your Python script to something which never reads from standard input. You can get the same result by piping to any command which doesn't read standard input, such as
python testscript.py | cd .
Or for a simpler example, consider a script printer.py containing nothing more than
print 'abcde'
Then
python printer.py | python printer.py
will produce the same error.
The following however will trap the sys.excepthook error:
import sys
import logging
def log_uncaught_exceptions(exception_type, exception, tb):
logging.critical(''.join(traceback.format_tb(tb)))
logging.critical('{0}: {1}'.format(exception_type, exception))
sys.excepthook = log_uncaught_exceptions
print "abcdfe"

Python - How to make sure that a line being read from a file contain only a given string and nothing else

In order to make sure I start and stop reading a text file exactly where I want to, I am providing 'start1'<->'end1', 'start2'<->'end2' as tags in between the text file and providing that to my python script. In my script I read it as:
start_end = ['start1','end1']
line_num = []
with open(file_path) as fp1:
for num, line in enumerate(fp1, 1):
for i in start_end:
if i in line:
line_num.append(num)
fp1.close()
print '\nLine number: ', line_num
fp2 = open(file_path)
for k, line2 in enumerate(fp2):
for x in range(line_num[0], line_num[1] - 1):
if k == x:
header.append(line2)
fp2.close()
This works well until I reach start10 <-> end10 and further. Eg. it checks if I have "start2" in the line and also reads the text that has "start21" and similarly for end tag as well. so providing "start1, end1" as input also reads "start10, end10". If I replace the line:
if i in line:
with
if i == line:
it throws an error.
How can I make sure that the script reads the line that contains ONLY "start1" and not "start10"?

import re
prog = re.compile('start1$')
if prog.match(line):
print line
That should return None if there is no match and return a regex match object if the line matches the compiled regex. The '$' at the end of the regex says that's the end of the line, so 'start1' works but 'start10' doesn't.
or another way..
def test(line):
import re
prog = re.compile('start1$')
return prog.match(line) != None
> test('start1')
True
> test('start10')
False

Since your markers are always at the end of the line, change:
start_end = ['start1','end1']
to:
start_end = ['start1\n','end1\n']

You probably want to look into regular expressions. The Python re library has some good regex tools. It would let you define a string to compare your line to and it has the ability to check for start and end of lines.

If you can control the input file, consider adding an underscore (or any non-number character) to the end of each tag.
'start1_'<->'end1_'
'start10_'<->'end10_'
The regular expression solution presented in other answers is more elegant, but requires using regular expressions.

You can do this with find():
for num, line in enumerate(fp1, 1):
for i in start_end:
if i in line:
# make sure the next char isn't '0'
if line[line.find(i)+len(i)] != '0':
line_num.append(num)

Python printing a stringon two lines if string beginns with 'l'

so I have some code such as:
print(csv[0])
Genes = csv[0]
OutPut.write(Genes)
OutPut.write(',')
OutPut.write(csv[1])
OutPut.write(',')
try:
OutPut.write(csv[2])
except IndexError:
print("No Lethality")
OutPut.write('\n')
Basically csv has 3 objects and they should print out as this:
atp,10101010,lethal
But for some reason, if csv[0] so the first value, begining with an 'l' it is printed as:
l
sfsf,1010101010,Lethal
I have tried using a for loop etc but I always get the same issue and all the other lines which start without an 'l' work perfectly.
Thanks

It's not clear from your description why you are seeing multiple lines, here's alternative logic that may help you diagnose the problem.
Try:
OutPut.write(','.join(csv))
OutPut.write('\n' if len(csv) == 3 else "No Lethality\n")
Or:
from __future__ import print_function
print(','.join(csv), file=Output)

Piping my Python Program through another program

I'm trying to make program using Python.
I want to be able to pipe program through another program:
" #EXAMPLE " ./my_python | another programme "
Here is the code I have so far.
This code saves output to file:
#!/usr/bin/env python
import os, random, string
# This is not my own code
''' As far asi know, It belongs to NullUserException. Was found on stackoverflow.com'''
length = 8
chars = string.ascii_letters.upper()+string.digits
random.seed = (os.urandom(1024))
# my code
file_out = open('newRa.txt','w') # Create a 'FILE' to save Generated Passwords
list1=[]
while len(list1) < 100000:
list1.append(''.join(random.choice(chars) for i in range(length)))
for item in list1:
file_out.write('%s\n' % item)
file_out.close()
file_out1=open('test.txt','w')
for x in list1:
file_out1.write('%s\n' %x[::-1])
This is the code I have trying to pipe it through another program:
#!/usr/bin/env python
import os,string,random,sys
length = 8
chars = string.ascii_letters.upper()+string.digits
random.seed = (os.urandom(1024))
keep=[]
keep1=[]
while len(keep)<1000:
keep.append(''.join(random.choice(chars) for i in range(length)))
print '\n',keep[::-1]
for x in keep:
keep1.append(x[::-1])
while len(keep1) < 1000:
print keep1
I have tried chmod and using the script as a executable.

Ok sorry for my lack of google search.
sys.stdout is the answer
#!/usr/bin/env python
import os,string,random,sys
length = 8
chars = string.ascii_letters.upper()+string.digits
random.seed = (os.urandom(1024))
keep=[]
while len(keep)<1000:
keep = (''.join(random.choice(chars) for i in range(length)))
print sys.stdout.write(keep)
sys.stdout.flush()
I stripped my code down (as it makes it a lot faster, But I'm getting this when execute
my code........
P5DBLF4KNone
DVFV3JQVNone
CIMKZFP0None
UZ1QA3HTNone
How do I get rid of the 'None' on the end?
What I have done to cause this ?
Should This Be A Seperate Question??

Comparing two strings in Python - depends on string source...?

I have the following python script:
import sys
import io
str1 = 'asd'
str2 - 'asd'
if (str2.find(str1)==-1):
print('FALSE')
else:
print('TRUE')
#Prints "TRUE"
It works fine. No problem. The problem starts if I take the string, put it in a file (save it) and then read the content of the file to str1 and str2, like so:
import sys
import io
fHandler = open(r'C:\dev\1.pub','r')
str1 = fHandler.read()
str2 = fHandler.read()
if (str2.find(str1)==-1):
print('FALSE')
else:
print('TRUE')
#Prints "FALSE"
Why is the behaviour different?
Thanks!

If you try to call fHandler.read() twice, then the second one will return n empty string (or empty bytes if you read binary). fHandler.read() reads everything until the end and the second call will start reading at the end until the end, so it returns an empty string. Try adding fHandler.seek(0) beetween your function calls and it should work.