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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")
share
|
impr...
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
...
How can I check the extension of a file?
...
os.path provides many functions for manipulating paths/filenames. (docs)
os.path.splitext takes a path and splits the file extension from the end of it.
import os
filepaths = ["/folder/soundfile.mp3", "folder1/folder/sound...
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 ...
Why is the apt-get function not working in the terminal on Mac OS X v10.9 (Mavericks)?
...
Mac OS X doesn't have apt-get. There is a package manager called Homebrew that is used instead.
This command would be:
brew install python
Use Homebrew to install packages that you would otherwise use apt-get for.
The page I li...
What kind of virtual machine is BEAM (the Erlang VM)?
...
The Erlang VM runs as one OS process. By default it runs one OS thread per core to achieve maximum utilisation of the machine. The number of threads and on which cores they run can be set when the VM is started.
Erlang processes are implemented entir...
Create empty file using python [duplicate]
I'd like to create a file with path x using python. I've been using os.system(y) where y = 'touch %s' % (x) . I've looked for a non-directory version of os.mkdir , but I haven't been able to find anything. Is there a tool like this to create a file without opening it, or using system or popen/...
Is gcc's __attribute__((packed)) / #pragma pack unsafe?
...cked__)) my_struct {
char c;
int i;
};
struct my_struct a = {'a', 123};
struct my_struct *b = &a;
int c = a.i;
int d = b->i;
int *e __attribute__((aligned(1))) = &a.i;
int *f = &a.i;
Here, the type of a is a packed struct (as defined above). Similarly, b is a pointer to a p...
How to get a list of installed android applications and pick one to run
...ng with a server. Is there any guidelines?
– dowjones123
Jun 30 '15 at 20:07
1
@dowjones123 Did u...
How do I upgrade PHP in Mac OS X?
... may want to check out Marc Liyanage's PHP package. It comes in a nice Mac OS X installer package that you can double-click. He keeps it pretty up to date.
http://php-osx.liip.ch/
Also, although upgrading to Snow Leopard won't help you do PHP updates in the future, it will probably give you a newe...