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How to create a directory and give permission in single command
... in the path you type. For example, mkdir -p -m 707 one/two/three. Even if all three directories are newly created, only the last one will have the requested permissions, and the others, default. install -d -m is broken the same way.
– Display Name
May 6 '15 at...
Cosmic Rays: what is the probability they will affect a program?
...rom Wikipedia:
Studies by IBM in the 1990s suggest that computers typically experience about one cosmic-ray-induced error per 256 megabytes of RAM per month.[15]
This means a probability of 3.7 × 10-9 per byte per month, or 1.4 × 10-15 per byte per second. If your program runs for 1 minute a...
Differences between Octave and MATLAB? [closed]
...uctures are. The above link shows several examples where they are syntactically similar or identical, is this true for the whole language?
...
How does one reorder columns in a data frame?
... has four columns like so df[,c(1,2,3,4)].
Note the first comma means keep all the rows, and the 1,2,3,4 refers to the columns.
To change the order as in the above question do df2[,c(1,3,2,4)]
If you want to output this file as a csv, do write.csv(df2, file="somedf.csv")
...
Is there a Python equivalent to Ruby's string interpolation?
... I understand the basic gist of it, I don't fully understand all the additional symbols and text found in the example in the documentation however. Why the use of convert to string here: %(language)s What does the 3 in '03d' signify? Why after the string is there % \? The assignmen...
What is the significance of ProjectTypeGuids tag in the visual studio project file
...
Do you really need a new project type if it is a project with .xaml and .cs files? If you do, I think you'll have to use a different Guid.
– Julien Hoarau
May 26 '10 at 11:33
...
Difference between Activity Context and Application Context
...nformation about the current activity that is necessary to complete those calls. If you show the exact error message, might be able to point to what exactly it needs.
But in general, use the activity context unless you have a good reason not to.
...
Catch multiple exceptions in one line (except block)
...t be in a tuple for catching to work as expected.
– BallpointBen
Mar 22 '18 at 16:02
8
Why would ...
What is the use of the %n format specifier in C?
...f characters printed thus far to an int variable), but so far no one has really given an example of what use it has. Here is one:
int n;
printf("%s: %nFoo\n", "hello", &n);
printf("%*sBar\n", n, "");
will print:
hello: Foo
Bar
with Foo and Bar aligned. (It's trivial to do that with...
iPhone app signing: A valid signing identity matching this profile could not be found in your keycha
...utton "Renew". After renewing and downloading updated provisioning profile all seems to work as expected, so problem is definitely solved :)
Update: you may have to contact Apple to get a "Renew"-button, or they removed it -- and the solution is to just download it and add it to the keychain, no ne...