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JavaScript “new Array(n)” and “Array.prototype.map” weirdness
... and constructs a new array from the results. callback is invoked only for indexes of the array which have assigned values; it is not invoked for indexes which have been deleted or which have never been assigned values." In this case, x's values have not explicitly assigned values, whereas y's were...
Accessing dict_keys element by index in Python3
I'm trying to access a dict_key's element by its index:
6 Answers
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Using DNS to redirect to another URL with a path [closed]
... subdomains, so instead of:
www.proof.com IN CNAME www.proof-two.com/path/index.htm
You could use:
www.proof.com IN CNAME proof.proof-two.com
then go to wherever you host proof-two.com and set it to point proof.proof-two.com to www.proof-two.com/path/index.htm.
~ there's always more than one wa...
Algorithm to compare two images
...tricky).
http://en.wikipedia.org/wiki/RGB_color_space
http://upvector.com/index.php?section=tutorials&subsection=tutorials/colorspace
Another example involves something called the Hough Transform. This transform essentially decomposes an image into a set of lines. You can then take some of...
add created_at and updated_at fields to mongoose schemas
...ut do you remember by any chance if fields created this way can be used as index?
– manidos
Aug 25 '17 at 18:31
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Google App Engine: Is it possible to do a Gql LIKE query?
...adful for a well populated table.
In other words, every query must use an index. This is why you can only do =, > and < queries. (In fact you can also do != but the API does this using a a combination of > and < queries.) This is also why the development environment monitors all the qu...
Why does “pip install” inside Python raise a SyntaxError?
...tructions for installing IPython: ipython.readthedocs.io/en/stable/install/index.html $ pip install ipython. Presumably that would translate to $ python -m pip install ipython
– Dan
Sep 13 '16 at 17:37
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vector::at vs. vector::operator[]
...bugs in your code. If you need to bounds-check at runtime because e.g. the index comes from user input, you're indeed best off with an if statement. So in summary, design your code with the intention that vector::at() will never throw an exception, so that if it does, and your program aborts, it's a...
Maximum size of an Array in Javascript
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No need to trim the array, simply address it as a circular buffer (index % maxlen). This will ensure it never goes over the limit (implementing a circular buffer means that once you get to the end you wrap around to the beginning again - not possible to overrun the end of the array).
For ex...
How do I modify fields inside the new PostgreSQL JSON datatype?
... create_missing boolean default true)
path can contain JSON array indexes too & negative integers that appear there count from the end of JSON arrays. However, a non-existing, but positive JSON array index will append the element to the end of the array:
SELECT jsonb_set('{"a":[null,{"b...