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What is the difference between int, Int16, Int32 and Int64?
What is the difference between int , System.Int16 , System.Int32 and System.Int64 other than their sizes?
10 Answers
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What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
...erally stated as a problem in Object-Relational mapping (ORM) discussions, and I understand that it has something to do with having to make a lot of database queries for something that seems simple in the object world.
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How do I compare version numbers in Python?
...lity but is used by setuptools (so you probably already have it installed) and is conformant to the current PEP 440; it will return a packaging.version.Version if the version is compliant and a packaging.version.LegacyVersion if not. The latter will always sort before valid versions.
Note: packagin...
How do I get both STDOUT and STDERR to go to the terminal and a log file?
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Use "tee" to redirect to a file and the screen. Depending on the shell you use, you first have to redirect stderr to stdout using
./a.out 2>&1 | tee output
or
./a.out |& tee output
In csh, there is a built-in command called "script" that...
How to profile a bash shell script slow startup?
...bashstart.PID.log that shows the seconds.nanoseconds timestamp of each command that was executed. The difference from one time to the next is the amount of time that the intervening step took.
As you narrow things down, you can move set -x later and set +x earlier (or bracket several sections of in...
Using async/await for multiple tasks
....Select(i => DoSomething(1, i, blogClient)).ToArray());
On the other hand, the above code with WaitAll also blocks the threads and your threads won't be free to process any other work till the operation ends.
Recommended Approach
I would prefer WhenAll which will perform your operations asyn...
Big O, how do you calculate/approximate it?
Most people with a degree in CS will certainly know what Big O stands for .
It helps us to measure how well an algorithm scales.
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Center a map in d3 given a geoJSON object
... you have a geoJSON object that you are going to draw you have to scale it and translate it in order to get it to the size that one wants and translate it in order to center it. This is a very tedious task of trial and error, and I was wondering if anyone knew a better way to obtain these values?
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Grouping functions (tapply, by, aggregate) and the *apply family
...ed by the extremely popular plyr package, the base functions remain useful and worth knowing.
This answer is intended to act as a sort of signpost for new useRs to help direct them to the correct *apply function for their particular problem. Note, this is not intended to simply regurgitate or repla...
Regular expression to match numbers with or without commas and decimals in text
I'm trying to locate and replace all numbers in a body of text. I've found a few example regex's, which almost solve the problem, but none are perfect yet. The problem I have is that the numbers in my text may or may not have decimals and commas. For example:
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