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Fast check for NaN in NumPy
...hine it is about 2.5x faster to use numpy.sum in place of numpy.min:
In [13]: %timeit np.isnan(np.min(x))
1000 loops, best of 3: 244 us per loop
In [14]: %timeit np.isnan(np.sum(x))
10000 loops, best of 3: 97.3 us per loop
Unlike min, sum doesn't require branching, which on modern hardware tends...
How to add an empty column to a dataframe?
...
463
If I understand correctly, assignment should fill:
>>> import numpy as np
>>>...
Can I zip more than two lists together in Scala?
...
36
I don't believe it's possible to generate a list of tuples of arbitrary size, but the transpose...
Working with $scope.$emit and $scope.$on
...trl:
function firstCtrl($scope)
{
$scope.$broadcast('someEvent', [1,2,3]);
}
function secondCtrl($scope)
{
$scope.$on('someEvent', function(event, mass) { console.log(mass); });
}
In case there is no parent-child relation between your scopes you
can inject $rootScope into the controller a...
LINQ where vs takewhile
...d find all elements matching the condition
var intList = new int[] { 1, 2, 3, 4, 5, -1, -2 };
Console.WriteLine("Where");
foreach (var i in intList.Where(x => x <= 3))
Console.WriteLine(i);
Console.WriteLine("TakeWhile");
foreach (var i in intList.TakeWhile(x => x <= 3))
Console....
Datatype for storing ip address in SQL Server
...
130
The technically correct way to store IPv4 is binary(4), since that is what it actually is (no, ...
How to use filter, map, and reduce in Python 3
...
352
You can read about the changes in What's New In Python 3.0. You should read it thoroughly when...
Sorting multiple keys with Unix sort
...
Ken GentleKen Gentle
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7
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Paste multiple columns together
...
# your starting data..
data <- data.frame('a' = 1:3, 'b' = c('a','b','c'), 'c' = c('d', 'e', 'f'), 'd' = c('g', 'h', 'i'))
# columns to paste together
cols <- c( 'b' , 'c' , 'd' )
# create a new column `x` with the three columns collapsed together
data$x <- apply( d...