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Why are Where and Select outperforming just Select?
...ver the entire set and, for each item, performs a conditional branch (checking for validity) and a + operation.
Where+Select creates an iterator that skips invalid elements (doesn't yield them), performing a + only on the valid items.
So, the cost for a Select is:
t(s) = n * ( cost(check valid...
Delete everything in a MongoDB database
I'm doing development on MongoDB. For totally non-evil purposes, I sometimes want to blow away everything in a database—that is, to delete every single collection, and whatever else might be lying around, and start from scratch. Is there a single line of code that will let me do this? Bonus points...
How to delete a character from a string using Python
There is a string, for example. EXAMPLE .
16 Answers
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Cannot obtain value of local or argument as it is not available at this instruction pointer, possibl
Visual Studio 2010 kills (there is no other word) data in one of the arguments of the function in the unsafe block.
What could cause this error? The following message shows by the debugger.
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What is the most elegant way to remove a path from the $PATH variable in Bash?
Or more generally, how do I remove an item from a colon-separated list in a Bash environment variable?
33 Answers
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Why is @font-face throwing a 404 error on woff files?
I'm using @font-face on my company's site and it works/looks great. Except Firefox and Chrome will throw a 404 error on the .woff file. IE does not throw the error. I have the fonts located at the root but I've tried with the fonts in the css folder and even giving the entire url for the font. I...
What are the differences between numpy arrays and matrices? Which one should I use?
...er the official documents, it's not anymore advisable to use matrix class since it will be removed in the future.
https://numpy.org/doc/stable/reference/generated/numpy.matrix.html
As other answers already state that you can achieve all the operations with NumPy arrays.
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How to use multiple arguments for awk with a shebang (i.e. #!)?
I'd like to execute an gawk script with --re-interval using a shebang. The "naive" approach of
10 Answers
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How does origin/HEAD get set?
I have a branch set up to track a ref in origin. git checkout <branchname> switches to that branch, and a git status will show me how far ahead or behind my branch is from origin, but I'm surprised that origin/HEAD still points at origin/master , and not origin/<branchname>
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How do I inject a controller into another controller in AngularJS
I'm new to Angular and trying to figure out how to do things...
7 Answers
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