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Javascript - get array of dates between 2 dates
...e 30 days before where should i change the above code to get only date not time.
– vaibhav kulkarni
Jul 22 '15 at 7:27
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How do you get the magnitude of a vector in Numpy?
...
mag = np.sqrt(x.dot(x))
Here are some benchmarks:
>>> import timeit
>>> timeit.timeit('np.linalg.norm(x)', setup='import numpy as np; x = np.arange(100)', number=1000)
0.0450878
>>> timeit.timeit('np.sqrt(x.dot(x))', setup='import numpy as np; x = np.arange(100)', num...
Java; String replace (using regular expressions)?
...attern? This might be useful if you do replaceAll with the same regex many times.
– qed
Nov 5 '14 at 20:35
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show 4 more comments
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Trim spaces from start and end of string
...cript performance this test is still relevant or reliable as it was at the time of this answer.
– Eduardo
Nov 30 '12 at 10:11
2
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How to count the number of set bits in a 32-bit integer?
...in, producing 8x 4-bit sums. The i - ... optimization isn't possible this time so it does just mask before / after shifting. Using the same 0x33... constant both times instead of 0xccc... before shifting is a good thing when compiling for ISAs that need to construct 32-bit constants in registers s...
How to create an alias for a command in Vim?
... This is the single best tip for vim. I'm so used to it now that every time I encounter the normal behavior, it takes me a few tried to get my mind retrained.
– airstrike
Feb 24 '15 at 19:58
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Seeding the random number generator in Javascript
...oose some dummy data to pad the seed with, and advance the generator a few times (12-20 iterations) to mix the initial state thoroughly. This is often seen in reference implementations of PRNGs, but it does limit the number of initial states.
var seed = 1337 ^ 0xDEADBEEF; // 32-bit seed with option...
Why do we copy then move?
...ion gets us nearly the same performance as the most-optimal version, but 2 times less code.
And if you are taking say 2 to 10 arguments, the reduction in code is exponential -- 2x times less with 1 argument, 4x with 2, 8x with 3, 16x with 4, 1024x with 10 arguments.
Now, we can get around this via...
str performance in python
...100000 is evaluated by the compiler and is equivalent to a constant at run-time.
>>> import dis
>>> dis.dis(lambda: str(100000))
8 0 LOAD_GLOBAL 0 (str)
3 LOAD_CONST 1 (100000)
6 CALL_FUNCTION 1
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How can I check if a URL exists via PHP?
...ax), this is quick to check server side.
Waiting for a response might take time and block code execution.
Not all headers returned by get_headers() are well formed.
Use curl (if you can).
Prevent fetching the entire body/content, but only request the headers.
Consider redirecting urls:
Do you want t...