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Why is Scala's immutable Set not covariant in its type?
...ameter of type A due to the contravariance of functions. Set could potentially be contravariant in A, but this too causes issues when you want to do things like this:
def elements: Iterable[A]
In short, the best solution is to keep things invariant, even for the immutable data structure. You'll...
Adjust UILabel height to text
...ne about some println's or just a line with only comments (then it says EXC_BAD_ACCESS code=2 as well)
– TheBurgerShot
Aug 8 '14 at 11:52
6
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What are best practices that you use when writing Objective-C and Cocoa? [closed]
...rogramming practices do you use when writing Objective-C, and more specifically when using Cocoa (or CocoaTouch).
33 Answer...
How can the Euclidean distance be calculated with NumPy?
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There's a function for that in SciPy. It's called Euclidean.
Example:
from scipy.spatial import distance
a = (1, 2, 3)
b = (4, 5, 6)
dst = distance.euclidean(a, b)
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List of Big-O for PHP functions
After using PHP for a while now, I've noticed that not all built-in PHP functions are as fast as expected. Consider these two possible implementations of a function that finds if a number is prime using a cached array of primes.
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adding noise to a signal in python
...umpy as np
import matplotlib.pyplot as plt
t = np.linspace(1, 100, 1000)
x_volts = 10*np.sin(t/(2*np.pi))
plt.subplot(3,1,1)
plt.plot(t, x_volts)
plt.title('Signal')
plt.ylabel('Voltage (V)')
plt.xlabel('Time (s)')
plt.show()
x_watts = x_volts ** 2
plt.subplot(3,1,2)
plt.plot(t, x_watts)
plt.title...
Select columns from result set of stored procedure
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Here's a link to a pretty good document explaining all the different ways to solve your problem (although a lot of them can't be used since you can't modify the existing stored procedure.)
How to Share Data Between Stored Procedures
Gulzar's answer will work (it is document...
Check if object is a jQuery object
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isn't obj.__proto__.jquery instead of obj.constructor.prototype.jquery enough? just a bit short :)
– Axel
Jul 3 '17 at 9:35
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MySQL: determine which database is selected?
After calling mysql_select_db to grab a database, is there any way to later output the name of the database that is currently selected? This seems very basic but I couldn't find anything on php.net or stackoverflow (all results are for "no database selected").
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How to replace captured groups only?
...ding and following text:
str.replace(/(.*name="\w+)(\d+)(\w+".*)/, "$1!NEW_ID!$3")
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