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Does ARC support dispatch queues?
...
And now for the long answer…
If your deployment target is lower than iOS 6.0 or Mac OS X 10.8
You need to use dispatch_retain and dispatch_release on your queue. ARC does not manage them.
If your deployment target is iOS 6.0 or Mac OS X 10.8 or later
ARC will manage your queue for you. Yo...
How to get a variable value if variable name is stored as string?
...ariable_value="\$$variable_name"
fi
echo "$variable_value"
}
test=123
get_value_of test
# 123
test="\$(echo \"something nasty\")"
get_value_of test
# $(echo "something nasty")
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impr...
How to run a program without an operating system?
...ill only load a small block of code.
Many ARM boards let you do some of those things. Some have boot loaders to help you with basic setup.
Here you may find a great tutorial on how to do a basic operating system on a Raspberry Pi.
Edit:
This article, and the whole wiki.osdev.org will anwer most o...
How to properly create an SVN tag from trunk?
...revision of the trunk and "tag" it as well. the command: svn copy -r 123 "svn.example.com/project/trunk" "svn.example.com/project/tags/1.0" -m "Tagging, but using older revision (123)."
– granadaCoder
Oct 18 '11 at 16:39
...
Iterating through directories with Python
...with a simple print statement you can see that each file is found:
import os
rootdir = 'C:/Users/sid/Desktop/test'
for subdir, dirs, files in os.walk(rootdir):
for file in files:
print os.path.join(subdir, file)
If you still get errors when running the above, please provide the error...
Getting name of windows computer running python script?
...gt;>> import platform
>>> import socket
>>> import os
>>> platform.node()
'DARK-TOWER'
>>> socket.gethostname()
'DARK-TOWER'
>>> os.environ['COMPUTERNAME']
'DARK-TOWER'
sha...
Get OS-level system information
...answer the question correctly. All that data reefers to JVM and not to the OS...
– Alvaro
Feb 19 '14 at 10:33
I know t...
MySQL CONCAT returns NULL if any field contain NULL
...ate_name`,''),'-',COALESCE(`model`,''),'-',COALESCE(`ip`,''),'-',COALESCE(`os_type`,''),'-',COALESCE(`os_version`,'')) AS device_name
FROM devices
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...
How to force R to use a specified factor level as reference in a regression?
...
See the relevel() function. Here is an example:
set.seed(123)
x <- rnorm(100)
DF <- data.frame(x = x,
y = 4 + (1.5*x) + rnorm(100, sd = 2),
b = gl(5, 20))
head(DF)
str(DF)
m1 <- lm(y ~ x + b, data = DF)
summary(m1)
Now alter the factor ...
How do I make python wait for a pressed key?
... the user to press enter though.
One might want to use msvcrt ((Windows/DOS only) The msvcrt module gives you access to a number of functions in the Microsoft Visual C/C++ Runtime Library (MSVCRT)):
import msvcrt as m
def wait():
m.getch()
This should wait for a key press.
Additional info:...