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How to access the ith column of a NumPy multidimensional array?
...
>>> test[:,0]
array([1, 3, 5])
Similarly,
>>> test[1,:]
array([3, 4])
lets you access rows. This is covered in Section 1.4 (Indexing) of the NumPy reference. This is quick, at least in my experience. It's certainly much quicker tha...
All possible array initialization syntaxes
...s above, the first two could replace the string[] on the left with var (C# 3+), as the information on the right is enough to infer the proper type. The third line must be written as displayed, as array initialization syntax alone is not enough to satisfy the compiler's demands. The fourth could also...
Add new row to dataframe, at specific row-index, not appended?
...ll:
existingDF <- as.data.frame(matrix(seq(20),nrow=5,ncol=4))
r <- 3
newrow <- seq(4)
insertRow <- function(existingDF, newrow, r) {
existingDF[seq(r+1,nrow(existingDF)+1),] <- existingDF[seq(r,nrow(existingDF)),]
existingDF[r,] <- newrow
existingDF
}
> insertRow(existi...
Jasmine.js comparing arrays
...
346
Just did the test and it works with toEqual
please find my test:
http://jsfiddle.net/7q9N7/3...
How to get the Power of some Integer in Swift language?
...(radix), Double(power)))
}
// ...
// Then you can do this...
let i = 2 ^^ 3
// ... or
println("2³ = \(2 ^^ 3)") // Prints 2³ = 8
I used two carets so you can still use the XOR operator.
Update for Swift 3
In Swift 3 the "magic number" precedence is replaced by precedencegroups:
precedencegro...
Comparing strings with == which are declared final in Java
...
232
When you declare a String (which is immutable) variable as final, and initialize it with a comp...
Accessing items in an collections.OrderedDict by index
...oo', 'python')
>>> d.items()[1]
('bar', 'spam')
Note for Python 3.X
dict.items would return an iterable dict view object rather than a list. We need to wrap the call onto a list in order to make the indexing possible
>>> items = list(d.items())
>>> items
[('foo', 'pyth...
How to delete an element from an array in C#
...
342
If you want to remove all instances of 4 without needing to know the index:
LINQ: (.NET Frame...
How to split a string in shell and get the last field
Suppose I have the string 1:2:3:4:5 and I want to get its last field ( 5 in this case). How do I do that using Bash? I tried cut , but I don't know how to specify the last field with -f .
...
Find which version of package is installed with pip
...
As of pip 1.3, there is a pip show command.
$ pip show Jinja2
---
Name: Jinja2
Version: 2.7.3
Location: /path/to/virtualenv/lib/python2.7/site-packages
Requires: markupsafe
In older versions, pip freeze and grep should do the job nice...