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Double vs. BigDecimal?
I have to calculate some floating point variables and my colleague suggest me to use BigDecimal instead of double since it will be more precise. But I want to know what it is and how to make most out of BigDecimal ?
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Generate random numbers with a given (numerical) distribution
... You can then use the rvs() method of the distribution object to generate random numbers.
As pointed out by Eugene Pakhomov in the comments, you can also pass a p keyword parameter to numpy.random.choice(), e.g.
numpy.random.choice(numpy.arange(1, 7), p=[0.1, 0.05, 0.05, 0.2, 0.4, 0.2])
If you a...
Return type of '?:' (ternary conditional operator)
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Expressions don't have return types, they have a type and - as it's known in the latest C++ standard - a value category.
A conditional expression can be an lvalue or an rvalue. This is its value category. (This is somewhat of a simplification, in C++11 we have lvalues, xvalues a...
Named string formatting in C#
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There is no built-in method for handling this.
Here's one method
string myString = "{foo} is {bar} and {yadi} is {yada}".Inject(o);
Here's another
Status.Text = "{UserName} last logged in at {LastLoginDate}".FormatWith(user);
A third improved method p...
What is the difference between mutex and critical section?
... between the two of them. On my system for 1,000,000 uncontended acquires and releases, a mutex takes over one second. A critical section takes ~50 ms for 1,000,000 acquires.
Here's the test code, I ran this and got similar results if mutex is first or second, so we aren't seeing any other effect...
How to put the legend out of the plot
... 3], label='Line 1')
p2, = plt.plot([3, 2, 1], label='Line 2')
plt.legend(handles=[p1, p2], title='title', bbox_to_anchor=(1.05, 1), loc='upper left', prop=fontP)
As noted by Mateen Ulhaq, fontsize='xx-small' also works, without importing FontProperties.
plt.legend(handles=[p1, p2], title='title...
How do you pass multiple enum values in C#?
...ine the enum, just attribute it with [Flags], set values to powers of two, and it will work this way.
Nothing else changes, other than passing multiple values into a function.
For example:
[Flags]
enum DaysOfWeek
{
Sunday = 1,
Monday = 2,
Tuesday = 4,
Wednesday = 8,
Thursday = 16,
...
How to determine if a decimal/double is an integer?
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IMHO, the modulus operator and floating point numbers just don't mix in any way useful. The code suggested is incredibly confusing given the number of keystrokes used and will work almost nowhere outside of .NET languages. I would bet it's also much sl...
What are dictionary view objects?
...sentially what their name says: views are simply like a window on the keys and values (or items) of a dictionary. Here is an excerpt from the official documentation for Python 3:
>>> dishes = {'eggs': 2, 'sausage': 1, 'bacon': 1, 'spam': 500}
>>> keys = dishes.keys()
>>>...
How to make an immutable object in Python?
...butes can be accessed via [0] etc., but at least it's considerably shorter and provides the additional advantage of being compatible with pickle and copy.
namedtuple creates a type similar to what I described in this answer, i.e. derived from tuple and using __slots__. It is available in Python 2....