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Formatting Decimal places in R
...number of decimal places are displayed. This is often done for consistency and standardisation purposes rather than being concerned with significant figures.
Solution:
The following code shows exactly two decimal places for the number x.
format(round(x, 2), nsmall = 2)
For example:
format(roun...
Multi-Line Comments in Ruby?
...egin
Every body mentioned this way
to have multiline comments.
The =begin and =end must be at the beginning of the line or
it will be a syntax error.
=end
puts "Hello world!"
<<-DOC
Also, you could create a docstring.
which...
DOC
puts "Hello world!"
"..is kinda ugly and creates
a String ...
How to create and handle composite primary key in JPA
...
You can make an Embedded class, which contains your two keys, and then have a reference to that class as EmbeddedId in your Entity.
You would need the @EmbeddedId and @Embeddable annotations.
@Entity
public class YourEntity {
@EmbeddedId
private MyKey myKey;
@Column(name ...
printf format specifiers for uint32_t and size_t
...antic, then. It's probably going off the names of types in the source code and doesn't realize they're equivalent. I wonder what it would do with @KennyTM's answer... It certainly should be more portable.
– Cogwheel
Jul 2 '10 at 18:49
...
Why `null >= 0 && null
...utine that increments the value of a variable by 1 if its type is number and assigns 0 to the variable if not, where the variable is initially null or undefined .
...
How do I access command line arguments in Python?
...ython to create my project settings setup, but I need help getting the command line arguments.
8 Answers
...
Python equivalent of D3.js
...
G.add_edge(3,4)
G.add_edge(4,2)
# use 'with' if you are writing a script and want to serve this up forever
with d3py.NetworkXFigure(G, width=500, height=500) as p:
p += d3py.ForceLayout()
p.show()
share
|...
How do I move a redis database from one server to another?
I currently have a live redis server running on a cloud instance and I want to migrate this redis server to a new cloud instance and use that instance as my new redis server. If it were MySQL, I would export the DB from the old server and import it into the new server. How should I do this with redi...
Is there a /dev/null on Windows?
...
I think you want NUL, at least within a command prompt or batch files.
For example:
type c:\autoexec.bat > NUL
doesn't create a file.
(I believe the same is true if you try to create a file programmatically, but I haven't tried it.)
In PowerShell, you want $nu...
Do any JVM's JIT compilers generate code that uses vectorized floating point instructions?
... System.out.println("dotc(): " + (t3 - t2)/10000000 + " ns");
}
}
and Dot.h:
float ac[50], bc[50];
inline float dotc() {
float sum = 0;
for (int i = 0; i < 50; i++) {
sum += ac[i]*bc[i];
}
return sum;
}
We can compile and run that with JavaCPP using this comma...