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Purpose of Unions in C and C++
... it for non-overlapping periods of time. These people never meet, and generally don't know anything about each other. By properly managing the time-sharing of the rooms (i.e. by making sure different people don't get assigned to one room at the same time), a relatively small hotel can provide accomm...
Split delimited strings in a column and insert as new rows [duplicate]
I have a data frame as follow:
6 Answers
6
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Circular list iterator in Python
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Output:
a b c a b c ...
(Loops forever, obviously)
In order to manually advance the iterator and pull values from it one by one, simply call next(pool):
>>> next(pool)
'a'
>>> next(pool)
'b'
share...
Hashing a file in Python
...those bigger files in chunks!
import sys
import hashlib
# BUF_SIZE is totally arbitrary, change for your app!
BUF_SIZE = 65536 # lets read stuff in 64kb chunks!
md5 = hashlib.md5()
sha1 = hashlib.sha1()
with open(sys.argv[1], 'rb') as f:
while True:
data = f.read(BUF_SIZE)
i...
What does the 'b' character do in front of a string literal?
Apparently, the following is the valid syntax:
8 Answers
8
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Reading specific lines only
I'm using a for loop to read a file, but I only want to read specific lines, say line #26 and #30. Is there any built-in feature to achieve this?
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Throwing cats out of windows
Imagine you're in a tall building with a cat. The cat can survive a fall out of a low story window, but will die if thrown from a high floor. How can you figure out the longest drop that the cat can survive, using the least number of attempts?
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Can I have an IF block in DOS batch file?
...t, and the opening parenthesis.
I am setting @echo off to keep from seeing all of the statements printed to the console as they execute, and instead just see the output of those that specifically begin with echo.
I'm using the built-in ERRORLEVEL variable just as a test. Read more here
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MySQL/Amazon RDS error: “you do not have SUPER privileges…”
... The -f option will not make the errors go away, it will just allow the non-offending SQL statements in the file to be processed. From what I've read, RDS is choking on stored procedures in the dump file. Try creating a dump file without store procedures and see if that loads OK: mysqld...
How can I start PostgreSQL server on Mac OS X?
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The Homebrew package manager includes launchctl plists to start automatically. For more information, run brew info postgres.
Start manually
pg_ctl -D /usr/local/var/postgres start
Stop manually
pg_ctl -D /usr/local/var/postgres stop
Start automatically
"To have launchd start postgresql now and res...