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Should I use a data.frame or a matrix?
...2,3,5),"dog",1i) # a list
dim(M) <- c(2,3) # set dimensions
print(M) # print result
# [,1] [,2] [,3]
# [1,] 3.14 5 "dog"
# [2,] TRUE Numeric,3 0+1i
DF <- data.frame(M) # a data frame
print(DF)...
Is the != check thread safe?
...like this one.
The Java Memory Model (specified in JLS 17.4) specifies a set of preconditions under which one thread is guaranteed to see memory values written by another thread. If one thread attempts to read a variable written by another one, and those preconditions are not satisfied, then ther...
How do I convert an enum to a list in C#? [duplicate]
... I love, using LINQ:
public class EnumModel
{
public int Value { get; set; }
public string Name { get; set; }
}
public enum MyEnum
{
Name1=1,
Name2=2,
Name3=3
}
public class Test
{
List<EnumModel> enums = ((MyEnum[])Enum.GetValues(typeof(MyEnum))).Select(c => ...
What's the difference between the 'ref' and 'out' keywords?
...are always passed by value in C#, unless you use the ref specifier. If you set myval=somenewval, the effect is only in that function scope. The ref keyword would allow you to change myval to point to somenewval.
– JasonTrue
Apr 14 '10 at 23:21
...
How to determine if a number is a prime with regex?
I found the following code example for Java on RosettaCode :
4 Answers
4
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Measure time in Linux - time vs clock vs getrusage vs clock_gettime vs gettimeofday vs timespec_get?
... that this measure may have discontinuities if you change some system time setting while your program runs.
C++11 chrono
Since we're at it, let's cover them as well: http://en.cppreference.com/w/cpp/chrono
GCC 5.3.0 (C++ stdlib is inside GCC source):
high_resolution_clock is an alias for system...
How does lucene index documents?
...ts, the index can be traversed from one hit to another, making things like set and, particularly, range queries possible (much like B-Trees). And the Wikipedia entry on indexing Skip-Lists also explains why Lucene's Skip-List implementation is called a multi-level Skip-List - essentially, to make O(...
Best way to resolve file path too long exception
...anged the current directory to the directory of the folder using Directory.SetCurrentDirectory() would it avoid this restriction. Or would the problem still exist.
– Adam Lindsay
Feb 17 '17 at 15:46
...
In HTML5, should the main navigation be inside or outside the element?
...n a header simply because that's where navigation often goes, but it's not set in stone.
You can read more about it at HTML5 Doctor.
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What is the difference between a map and a dictionary?
...y of Computer Science lists:
dictionary any data structure representing a set of elements that can support the insertion and deletion of elements as well as test for membership
For example, we have a set of elements { A, B, C, D... } that we've been able to insert and could start deleting, and we...