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How to remove a key from a Python dictionary?
...osentino No, ignoring the return value of a function is not inefficient at all. Quite the opposite – this solution is much faster than the try/except solution if the key does not exist. You might find one or the other easier to read, which is fine. Both are idiomatic Python, so choose whatever ...
Assign same value to multiple variables at once?
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@Eoin: In doing $var_a = $var_b = ... = new Class();, all the variables will reference the same instance of Class.
– Tim Cooper
Jun 21 '19 at 19:34
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Is there a best practice for generating html with javascript
I'm calling a web service that returns an array of objects in JSON. I want to take those objects and populate a div with HTML. Let's say each object contains a url and a name.
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Why is 1/1/1970 the “epoch time”?
...ess than 829 days. For this reason, the time represented by the number 0 (called the epoch) had to be set in the very recent past. As this was in the early 1970s, the epoch was set to 1971-1-1.
Later, the system time was changed to increment every second, which increased the span of time that could...
css z-index lost after webkit transform translate3d
...s might be related to: https://bugs.webkit.org/show_bug.cgi?id=61824
Basically when you apply a 3D transform on the z-axis, the z-index can't be accounted for anymore (you're now in a 3 dimensional rendering plane, use different z-values). If you want to switch back to 2D rendering for child elemen...
How to get the directory of the currently running file?
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It actually works even if os.Args[0] does not contain the abs path. The reason the playground result is not what you expected is because it is inside a sandbox.
– Gustavo Niemeyer
Jul 21 '15 at...
Cron job every three days
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The answer is not correct because neither suggestion actually runs the job every 3 days. 0 0 */3 * * means run on the 1st, 4th, 7th, etc. (*/3 means 1-31/3 means 1,4,7...31) so the gap will be smaller at the end of the month. (It'll run 2 days in a row if the previous month had 3...
What happens when a duplicate key is put into a HashMap?
...laces the previous value associated with the given key in the map (conceptually like an array indexing operation for primitive types).
The map simply drops its reference to the value. If nothing else holds a reference to the object, that object becomes eligible for garbage collection. Additionall...
Check time difference in Javascript
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I know this is ancient, but where in all this gibberish does anything get read from form fields? All I see is some hard-coded example code. How do I get the difference between whatever times my user typed into my two input type="text" boxes, rather than between ...
what is the difference between 'transform' and 'fit_transform' in sklearn
...is meant for when you have already computed PCA, i.e. if you have already called its .fit method.
In [12]: pc2 = RandomizedPCA(n_components=3)
In [13]: pc2.transform(X) # can't transform because it does not know how to do it.
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