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Return first N key:value pairs from dict
...no longer correct. Python dicts now preserve insertion order, and this is explicitly documented.
– Konrad Rudolph
Sep 22 at 12:30
1
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StringBuilder vs String concatenation in toString() in Java
...rom the question (compiled on JDK 1.6.0_16) and found the optimization as expected. I'm pretty sure all modern compilers will do it.
– Michael Borgwardt
Oct 7 '09 at 16:12
22
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How are people managing authentication in Go? [closed]
...ere is a lot of latent interest in this topic, and many people are asking exactly the same thing and not finding answers on the Interwebs.
Most of the available information results in the textual equivalent of the hand wavy thing, left as an "exercise for the reader." ;)
However I've finally locat...
How to get duplicate items from a list using LINQ? [duplicate]
...t actually return all duplicate records, it returns all duplicate records EXCEPT for the first occurrence in each group. So yes, if you're after a list of just the distinct duplicate values then this answer, with the Distinct method is the way to go, but if you want all the duplicate rows, then Scot...
What is the difference between 'my' and 'our' in Perl?
I know what my is in Perl. It defines a variable that exists only in the scope of the block in which it is defined. What does our do?
...
returning in the middle of a using block
...ou didn't return and simply kept a reference to a variable.
using ( var x = new Something() ) {
// not a good idea
return x;
}
Just as bad
Something y;
using ( var x = new Something() ) {
y = x;
}
share
...
combinations between two lists?
...2. In python:
import itertools
list1=['a','b','c']
list2=[1,2]
[list(zip(x,list2)) for x in itertools.permutations(list1,len(list2))]
Returns
[[('a', 1), ('b', 2)], [('a', 1), ('c', 2)], [('b', 1), ('a', 2)], [('b', 1), ('c', 2)], [('c', 1), ('a', 2)], [('c', 1), ('b', 2)]]
...
How to make graphics with transparent background in R using ggplot2?
...save() and the code for the legend background:
df <- data.frame(y = d, x = 1, group = rep(c("gr1", "gr2"), 50))
p <- ggplot(df) +
stat_boxplot(aes(x = x, y = y, color = group),
fill = "transparent" # for the inside of the boxplot
)
Fastest way is using using rect, as al...
Why are these numbers not equal?
...eral (language agnostic) reason
Since not all numbers can be represented exactly in IEEE floating point arithmetic (the standard that almost all computers use to represent decimal numbers and do math with them), you will not always get what you expected. This is especially true because some values ...
How to unset a JavaScript variable?
...erty is defined.
(1) If it is created with var, it cannot be deleted.
For example:
var g_a = 1; //create with var, g_a is a variable
delete g_a; //return false
console.log(g_a); //g_a is still 1
(2) If it is created without var, it can be deleted.
g_b = 1; //create without var, g_b is a property
...