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Execution time of C program
...Windows machines (from the Win98 era) it was closer to 60ms.
clock() is standard C; it works "everywhere". There are system-specific functions, such as getrusage() on Unix-like systems.
Java's System.currentTimeMillis() does not measure the same thing. It is a "wall clock": it can help you measure...
MySQL COUNT DISTINCT
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Select
Count(Distinct user_id) As countUsers
, Count(site_id) As countVisits
, site_id As site
From cp_visits
Where ts >= DATE_SUB(NOW(), INTERVAL 1 DAY)
Group By site_id
...
Binding a WPF ComboBox to a custom list
I have a ComboBox that doesn't seem to update the SelectedItem/SelectedValue.
4 Answers
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Rails :include vs. :joins
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.joins will just joins the tables and brings selected fields in return. if you call associations on joins query result, it will fire database queries again
:includes will eager load the included associations and add them in memory. :includes loads all the included tabl...
Cross-browser custom styling for file upload button [duplicate]
... This works great for me, my only issue is that after a file is selected, it doesn't actually show that a file has been selected. Is there any way to show an indicator that a file has been chosen?
– Dylan Vester
Feb 27 '15 at 21:27
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Performing Breadth First Search recursively
... traversal traditionally uses a queue, not a stack. The nature of a queue and a stack are pretty much opposite, so trying to use the call stack (which is a stack, hence the name) as the auxiliary storage (a queue) is pretty much doomed to failure, unless you're doing something stupidly ridiculous w...
Get MD5 hash of big files in Python
I have used hashlib (which replaces md5 in Python 2.6/3.0) and it worked fine if I opened a file and put its content in hashlib.md5() function.
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iPhone Debugging: How to resolve 'failed to get the task for process'?
...but resolved it by following simple following steps :
Make sure you have selected debug rather than release.
In Debug configurations, in project settings, you should have selected developer's profile & no need of specifying the entitlements plist.
Also same setting are there under: Targets: , ...
How to tell git to use the correct identity (name and email) for a given project?
I use my personal laptop for both work and personal projects and I would like to use my work email address for my commits at work (gitolite) and my personal email address for the rest (github).
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Is it possible to install another version of Python to Virtualenv?
...] DEST_DIR
Options:
--version show program's version number and exit.
-h, --help show this help message and exit.
-v, --verbose Increase verbosity.
-q, --quiet Decrease verbosity.
-p PYTHON_EXE, --python=PYTHON_EXE
The Pytho...