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Compare two data.frames to find the rows in data.frame 1 that are not present in data.frame 2
...re allowed (e.g. changing order of elements of each vector, changing order and names of variables, shortening variables, changing case of strings). From this, you should be able to figure out what was missing from one or the other. For example (this is not very elegant):
difference <-
data.fr...
Value of i for (i == -i && i != 0) to return true in Java
...000000000000000000
Taking the negative value is done by first swapping 0 and 1, which gives
01111111111111111111111111111111
and by adding 1, which gives
10000000000000000000000000000000
As you can see in the link I gave, Wikipedia mentions the problem with the most negative numbers and spec...
How to upgrade Git on Windows to the latest version?
...version 1.7.9.mysysgit.0. I downloaded the new version from the Git site and installed through the normal Git installer EXE.
...
Why should I use Hamcrest-Matcher and assertThat() instead of traditional assertXXX()-Methods
...ormation from assertTrue.
assertThat will tell you what the assertion was and what you got instead. assertTrue will only tell you that you got false where you expected true.
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Generate random numbers following a normal distribution in C/C++
How can I easily generate random numbers following a normal distribution in C or C++?
18 Answers
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Checking the equality of two slices
...
You need to loop over each of the elements in the slice and test. Equality for slices is not defined. However, there is a bytes.Equal function if you are comparing values of type []byte.
func testEq(a, b []Type) bool {
// If one is nil, the other must also be nil.
if (a ...
'and' (boolean) vs '&' (bitwise) - Why difference in behavior with lists vs numpy arrays?
What explains the difference in behavior of boolean and bitwise operations on lists vs NumPy arrays?
8 Answers
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Convert any object to a byte[]
I am writing a prototype TCP connection and I am having some trouble homogenizing the data to be sent.
13 Answers
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In C++, is it still bad practice to return a vector from a function?
...d Jun 28 '10 at 17:55
Peter AlexanderPeter Alexander
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What is the best way to test for an empty string in Go?
...
Both styles are used within the Go's standard libraries.
if len(s) > 0 { ... }
can be found in the strconv package: http://golang.org/src/pkg/strconv/atoi.go
if s != "" { ... }
can be found in the encoding/json package: http://golang.org/src/pkg/encoding/...