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Add characters to a string in Javascript
...r Loop characters to an empty string. I know that you can use the function concat in Javascript to do concats with strings
...
Most efficient way to prepend a value to an array
...g an array to the front of another array, it is more efficient to just use concat. So:
var newArray = values.concat(oldArray);
But this will still be O(N) in the size of oldArray. Still, it is more efficient than manually iterating over oldArray. Also, depending on the details, it may help you, b...
Why is string concatenation faster than array join?
Today, I read this thread about the speed of string concatenation.
9 Answers
9
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StringBuilder vs String concatenation in toString() in Java
...s it might not make a
difference, but at what point do you
switch from concat to builder?
At the point where you're concatenating in a loop - that's usually when the compiler can't substitute StringBuilder by itself.
s...
How can I return pivot table output in MySQL?
...nother way to generate a pivot table without using "if", "case", or "GROUP_CONCAT": en.wikibooks.org/wiki/MySQL/Pivot_table
– user2513149
Oct 16 '16 at 16:15
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How to concatenate strings in twig
Anyone knows how to concatenate strings in twig? I want to do something like:
11 Answers
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Are there pronounceable names for common Haskell operators? [closed]
...lt;|> or / alternative expr <|> term: "expr or term"
++ concat / plus / append
[] empty list
: cons
:: of type / as f x :: Int: f x of type Int
\ lambda
@ as go ll@(l:ls): go ll as l cons ls
~ lazy go ~(a,b): go la...
Iterate two Lists or Arrays with one ForEach statement in C#
...
You can use Union or Concat, the former removes duplicates, the later doesn't
foreach (var item in List1.Union(List1))
{
//TODO: Real code goes here
}
foreach (var item in List1.Concat(List1))
{
//TODO: Real code goes here
}
...
MySQL JOIN the most recent row only?
...
You may want to try the following:
SELECT CONCAT(title, ' ', forename, ' ', surname) AS name
FROM customer c
JOIN (
SELECT MAX(id) max_id, customer_id
FROM customer_data
GROUP BY customer_id
) c...
Creating dataframe from a dictionary where entries have different lengths
...
You can also use pd.concat along axis=1 with a list of pd.Series objects:
import pandas as pd, numpy as np
d = {'A': np.array([1,2]), 'B': np.array([1,2,3,4])}
res = pd.concat([pd.Series(v, name=k) for k, v in d.items()], axis=1)
print(res)
...