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How to access the last value in a vector?
...s not from an aesthetical but performance-oriented point of view, I've put all of the above suggestions through a benchmark. To be precise, I've considered the suggestions
x[length(x)]
mylast(x), where mylast is a C++ function implemented through Rcpp,
tail(x, n=1)
dplyr::last(x)
x[end(x)[1]]]
rev...
Calendar Recurring/Repeating Events - Best Storage Method
... didn't want to have a large number of rows, and I wanted to easily lookup all events that would take place on a specific date.
The method below is great at storing repeating information that occurs at regular intervals, such as every day, every n days, every week, every month every year, etc etc. ...
Django dynamic model fields
...rks)
This solution is based on Entity Attribute Value data model, essentially, it uses several tables to store dynamic attributes of objects. Great parts about this solution is that it:
uses several pure and simple Django models to represent dynamic fields, which makes it simple to understand an...
case-insensitive list sorting, without lowercasing the result?
...
In Python 3.3+ there is the str.casefold method that's specifically designed for caseless matching:
sorted_list = sorted(unsorted_list, key=str.casefold)
In Python 2 use lower():
sorted_list = sorted(unsorted_list, key=lambda s: s.lower())
It works for both normal and unicode strin...
How to reverse a string in Go?
...size of the input in bytes. It does not correspond to its length. - Not all utf8's runes are of the same size. It can be either 1, 2, 4, or 8. - You should use unicode/ut8 package's method RuneCountInString to get the length of the rune.
– Anvesh Checka
M...
Creating JS object with Object.create(null)?
...t.create(null) doesn't inherit from anything and thus has no properties at all.
In other words: A javascript object inherits from Object by default, unless you explicitly create it with null as its prototype, like: Object.create(null).
{} would instead be equivalent to Object.create(Object.prototy...
How to import a Python class that is in a directory above?
...on __file__ to find out the parent directory (a couple of os.path.dirname calls will do;-), then (if that directory is not already on sys.path) prepend temporarily insert said dir at the very start of sys.path, __import__, remove said dir again -- messy work indeed, but, "when you must, you must" (a...
Is there a way to make GHC provide the type class constraints of typed holes?
...ng out-of-scope types
(use -fprint-potential-instances to see them all)
• In the expression: show _
In an equation for ‘it’: it = show _
<interactive>:3:6: error:
• Found hole: _ :: a0
Where: ‘a0’ is an ambiguous type variable
• In the first argum...
Proper Linq where clauses
...collection where as in the first one, it's applying the first predicate to all items first and the result (which is narrowed down at this point) is used for the second predicate and so on. The results get narrowed down every pass but still it involves multiple passes.
Also the chaining (first metho...
Sphinx autodoc is not automatic enough
...for modules project.module1 and project.module2 will be generated automatically and placed into _autosummary directory.
PROJECT
=======
.. toctree::
.. autosummary::
:toctree: _autosummary
project.module1
project.module2
By default autosummary will generate only very short summaries fo...
