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How do I convert seconds to hours, minutes and seconds?
...his is the best way, IMHO, as you can then use arithmetic on the timedelta and any datetime objects.
– Matthew Schinckel
Apr 22 '09 at 3:13
13
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How to append rows to an R data frame
...rs of the type you want for each column, insert values into those vectors, and then, at the end, create your data.frame.
Continuing with Julian's f3 (a preallocated data.frame) as the fastest option so far, defined as:
# pre-allocate space
f3 <- function(n){
df <- data.frame(x = numeric(n)...
Generating random integer from a range
I need a function which would generate a random integer in given range (including border values). I don't unreasonable quality/randomness requirements, I have four requirements:
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How does one make random number between range for arc4random_uniform()?
so my goal in this codebit is to randomly roll two dice and as we all know your regular die only has 6 sides so I imported Foundation for access to arc4random_uniform(UInt32). I attempted using the range of (1..7) to avoid randomly getting 0 however that returned an error which I didn't enjoy too mu...
PowerShell script to return versions of .NET Framework on a machine?
...swers both return the root number on my system for .NET 3.0 (where the WCF and WPF numbers, which are nested under 3.0, are higher -- I can't explain that), and fail to return anything for 4.0 ...
EDIT: For .Net 4.5 and up, this changed slightly again, so there's now a nice MSDN article here expla...
Under what circumstances are linked lists useful?
... with a single CAS (+retries).
In a modern GC-d environment - such as Java and .NET - the ABA problem can easily be avoided.
Just wrap items you add in freshly created nodes and do not reuse those nodes - let the GC do its work.
The page on the ABA problem also provides the implementation of a lock...
Way to get number of digits in an int?
...thematically, numbers don't have a length, nor do they have digits. Length and digits are both properties of a physical representation of a number in a specific base, i.e. a String.
A logarithm-based solution does (some of) the same things the String-based one does internally, and probably does so ...
Redirect Windows cmd stdout and stderr to a single file
I'm trying to redirect all output (stdout + stderr) of a DOS command to a single file:
7 Answers
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Finding local IP addresses using Python's stdlib
... addresses (i.e. 192.168.x.x or 10.0.x.x) in Python platform independently and using only the standard library?
45 Answers
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Best practices for circular shift (rotate) operations in C++
Left and right shift operators (>) are already available in C++.
However, I couldn't find out how I could perform circular shift or rotate operations.
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