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How do I loop through a list by twos? [duplicate]
I want to loop through a Python list and process 2 list items at a time. Something like this in another language:
7 Answers...
Real life example, when to use OUTER / CROSS APPLY in SQL
...me,
pa.name
FROM sys.procedures pr
OUTER APPLY (SELECT TOP 2 *
FROM sys.parameters pa
WHERE pa.object_id = pr.object_id
ORDER BY pr.name) pa
ORDER BY pr.name,
pa.name
2) Calling a Table Valued Function for ...
Why can't R's ifelse statements return vectors?
...st vectors, you will get longer results:
> ifelse(c(TRUE, FALSE), c(1, 2), c(3, 4))
[1] 1 4
So ifelse is intended for the specific purpose of testing a vector of booleans and returning a vector of the same length, filled with elements taken from the (vector) yes and no arguments.
It is a comm...
javascript i++ vs ++i [duplicate]
...
207
The difference between i++ and ++i is the value of the expression.
The value i++ is the value...
Why use the params keyword?
...
With params you can call your method like this:
addTwoEach(1, 2, 3, 4, 5);
Without params, you can’t.
Additionally, you can call the method with an array as a parameter in both cases:
addTwoEach(new int[] { 1, 2, 3, 4, 5 });
That is, params allows you to use a shortcut when call...
Printing the correct number of decimal points with cout
I have a list of float values and I want to print them with cout with 2 decimal places.
12 Answers
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Sort hash by key, return hash in Ruby
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229
In Ruby 2.1 it is simple:
h.sort.to_h
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How to iterate a loop with index and element in Swift
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print("Item \(index): \(element)")
}
Before Swift 3.0 and after Swift 2.0, the function was called enumerate():
for (index, element) in list.enumerate() {
print("Item \(index): \(element)")
}
Prior to Swift 2.0, enumerate was a global function.
for (index, element) in enumerate(list) {
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How can I profile C++ code running on Linux?
... stack. If there is some code that is wasting some percentage of the time, 20% or 50% or whatever, that is the probability that you will catch it in the act on each sample. So, that is roughly the percentage of samples on which you will see it. There is no educated guesswork required. If you do have...
How to find the sum of an array of numbers
Given an array [1, 2, 3, 4] , how can I find the sum of its elements? (In this case, the sum would be 10 .)
43 Answers
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