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Preferred way to create a Scala list
...end is O(1).
– Daniel C. Sobral
Aug 31 '15 at 19:33
@pgoggijr That is not true. First, there's no "change" anywhere, b...
Create numpy matrix filled with NaNs
...ed array and assign to all entries at once:
>>> a = numpy.empty((3,3,))
>>> a[:] = numpy.nan
>>> a
array([[ NaN, NaN, NaN],
[ NaN, NaN, NaN],
[ NaN, NaN, NaN]])
I have timed the alternatives a[:] = numpy.nan here and a.fill(numpy.nan) as posted by ...
Return multiple values in JavaScript?
...
1380
No, but you could return an array containing your values:
function getValues() {
return [...
Should all Python classes extend object?
... new-style classes.
Finally, old-style classes have disappeared in Python 3, and inheritance from object has become implicit. So, always prefer new style classes unless you need backward compat with old software.
share
...
Is there an R function for finding the index of an element in a vector?
... function match works on vectors :
x <- sample(1:10)
x
# [1] 4 5 9 3 8 1 6 10 7 2
match(c(4,8),x)
# [1] 1 5
match only returns the first encounter of a match, as you requested. It returns the position in the second argument of the values in the first argument.
For multiple matching, ...
What is the difference between String.slice and String.substring?
...
answered Feb 11 '10 at 10:36
Daniel VassalloDaniel Vassallo
301k6666 gold badges475475 silver badges424424 bronze badges
...
How to copy a dictionary and only edit the copy
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937
Python never implicitly copies objects. When you set dict2 = dict1, you are making them refer t...
Get the week start date and week end date from week number
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3
Bear in mind that setting DATEFIRST to anything other than 7 breaks this.
– Tomalak
Aug 12 '09 at 16:...
Validate phone number with JavaScript
...ctly. It validates that the phone number is in one of these formats:
(123) 456-7890 or 123-456-7890
26 Answers
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