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What is more efficient? Using pow to square or just multiply it with itself?
...cality of data, reducing the use of dynamic memory, pre-computing results, etc. They rarely ever come from micro-optimizing single function calls, and where they do, they do so in very few places, which would only be found by careful (and time-consuming) profiling, more often than never they can be ...
How to check whether a variable is a class or not?
...s this to isinstance(object, type). Note that objects like int, list, str, etc. are also classes, so you can't use this to distinguish between custom classes defined in Python and built-in classes defined in C code.
– Martijn Pieters♦
Jan 6 '18 at 14:27
...
Check if a temporary table exists and delete if it exists before creating a temporary table
...
The statement should be of the order
Alter statement for the table
GO
Select statement.
Without 'GO' in between, the whole thing will be considered as one single script and when the select statement looks for the column,it won't be found.
With 'GO' , ...
Python function overloading
...amp; ...) regular_bullet(...)
else if (...) curved_bullet(...)
//..etc..
}
Pass as many arguments to the c_function that exist, then do the job of determining which c function to call based on the values in the initial c function. So, python should only ever be calling the one c function. ...
What is the difference between LR, SLR, and LALR parsers?
... exactly the same size as the equivalent SLR grammar, which are usually an order of magnitude smaller than pure LR parsing tables. However, for LR grammars that are too complex to be LALR, these merged states result in parser conflicts, or produce a parser that does not fully recognize the original ...
Insert a commit before the root commit in Git?
...ids touching the working copy or the index or which branch is checked out, etc.
Create a tree object for an empty directory:
tree=`git hash-object -wt tree --stdin < /dev/null`
Wrap a commit around it:
commit=`git commit-tree -m 'root commit' $tree`
Create a reference to it:
git branch new...
How do I extract a sub-hash from a hash?
...
If you don't use rails, Hash#values_at will return the values in the same order as you asked them so you can do this:
def slice(hash, *keys)
Hash[ [keys, hash.values_at(*keys)].transpose]
end
def except(hash, *keys)
desired_keys = hash.keys - keys
Hash[ [desired_keys, hash.values_at(*desire...
How Do I 'git fetch' and 'git merge' from a Remote Tracking Branch (like 'git pull')
...le to merge them into the local branch once I have updated them with 'git fetch'.
5 Answers
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Relation between CommonJS, AMD and RequireJS?
...sically, CommonJS specifies that you need to have a require() function to fetch dependencies, an exports variable to export module contents and a module identifier (which describes the location of the module in question in relation to this module) that is used to require the dependencies (source). C...
How can the Euclidean distance be calculated with NumPy?
... b)))
move along. But if you're comparing distances, doing range checks, etc., I'd like to add some useful performance observations.
Let’s take two cases: sorting by distance or culling a list to items that meet a range constraint.
# Ultra naive implementations. Hold onto your hat.
def sort_t...