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Checking if a string can be converted to float in Python
I've got some Python code that runs through a list of strings and converts them to integers or floating point numbers if possible. Doing this for integers is pretty easy
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What should every developer know about databases? [closed]
...ither regularly work with databases or may have to work with one someday. And considering the amount of misuse and abuse in the wild, and the volume of database-related questions that come up every day, it's fair to say that there are certain concepts that developers should know - even if they don'...
Checking from shell script if a directory contains files
...{#files} -gt 0 ]; or maybe you just forgot the () around the sub-shell command? files=($(shopt -s nullglob;shopt -s dotglob;echo /some/dir/*))
– stoutyhk
Jul 4 '13 at 17:48
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Clang vs GCC - which produces faster binaries? [closed]
I'm currently using GCC, but I discovered Clang recently and I'm pondering switching. There is one deciding factor though - quality (speed, memory footprint, reliability) of binaries it produces - if gcc -O3 can produce a binary that runs 1% faster, or Clang binaries take up more memory or just fai...
What is a stream?
...n a stream:
read one byte. Next time you read, you'll get the next byte, and so on.
read several bytes from the stream into an array
seek (move your current position in the stream, so that next time you read you get bytes from the new position)
write one byte
write several bytes from an array into...
Best way to test SQL queries [closed]
...rrors. Essentially this results in sending mail to the incorrect customers and other 'problems' like that.
4 Answers
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Compare two dates with JavaScript
...uggest a way to compare the values of two dates greater than, less than, and not in the past using JavaScript? The values will be coming from text boxes.
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How to count the number of set bits in a 32-bit integer?
...ays addition'.
The 'best' algorithm really depends on which CPU you are on and what your usage pattern is.
Some CPUs have a single built-in instruction to do it and others have parallel instructions which act on bit vectors. The parallel instructions (like x86's popcnt, on CPUs where it's supported)...
bash: mkvirtualenv: command not found
...erage the chance that virtualenvwrapper.sh is already in your shell's PATH and just issue a source `which virtualenvwrapper.sh`
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What is the difference between an expression and a statement in Python?
In Python, what is the difference between expressions and statements?
14 Answers
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