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What's the difference between NOT EXISTS vs. NOT IN vs. LEFT JOIN WHERE IS NULL?
...ems to me that you can do the same thing in a SQL query using either NOT EXISTS, NOT IN, or LEFT JOIN WHERE IS NULL. For example:
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Getting distance between two points based on latitude/longitude
I tried implementing this formula: http://andrew.hedges.name/experiments/haversine/
The aplet does good for the two points I am testing:
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What is Ember RunLoop and how does it work?
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Update 10/9/2013: Check out this interactive visualization of the run loop: https://machty.s3.amazonaws.com/ember-run-loop-visual/index.html
Update 5/9/2013: all the basic concepts below are still up to date, but as of this commit, the Ember Run Loop imp...
HTTP authentication logout via PHP
What is the correct way to log out of HTTP authentication protected folder?
18 Answers
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ISO time (ISO 8601) in Python
.... In Python, I would like to take its creation time, and convert it to an ISO time (ISO 8601) string while preserving the fact that it was created in the Eastern Time Zone (ET) .
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Draw a perfect circle from user's touch
I have this practice project that allows the user to draw on the screen as they touch with their fingers. Very simple App I did as exercise way back.
My little cousin took the liberty of drawing things with his finger with my iPad on this App (Kids drawings: circle, lines, etc, whatever came to his ...
What are the “standard unambiguous date” formats for string-to-date conversion in R?
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This is documented behavior. From ?as.Date:
format: A character string. If not specified, it will try
'"%Y-%m-%d"' then '"%Y/%m/%d"' on the first non-'NA' element,
and give an error if neither work...
How to read/process command line arguments?
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The canonical solution in the standard library is argparse (docs):
Here is an example:
from argparse import ArgumentParser
parser = ArgumentParser()
parser.add_argument("-f", "--file", dest="filename",
help="write report to FILE", metavar="FILE")
pa...
Mod in Java produces negative numbers [duplicate]
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The problem here is that in Python the % operator returns the modulus and in Java it returns the remainder. These functions give the same values for positive arguments, but the modulus always returns positive results for negative input, wher...
How to hide action bar before activity is created, and then show it again?
I need to implement splash screen in my honeycomb app.
I use this code in activity's onCreate to show splash:
27 Answers
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