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What's the scope of a variable initialized in an if statement?
...ked only at runtime -- that is, when you get to the print x statement. If __name__ didn't equal "__main__" then you would get an exception: NameError: name 'x' is not defined.
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AngularJS For Loop with Numbers & Ranges
... You have to watch out for things like this. The range function will get called multiple times for each item in the list. You can get nasty memory leaks and you're generating a lot of function calls. It almost seems easier to put the collection inside the controller.
– Lucas ...
How to TryParse for Enum value?
....Val1|MyEnum.Val2" which is a combination of two enum values. If you just call Enum.IsDefined with this string, it will return false, even though Enum.Parse handles it correctly.
Update
As mentioned by Lisa and Christian in the comments, Enum.TryParse is now available for C# in .NET4 and up.
MSDN...
Zero-based month numbering [closed]
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The use of zero to start counting is actually an optimization trick from Assembly programmers. Instead of assigning 1 to the count register, they XOR'ed the register with itself, which was slightly faster in CPU cycles. This meant that counting would start with 0 an...
difference between fork and branch on github
If I fork a project that's hosted on github. Do I fork all the branches? How do I know which branch my fork is based on? In other words which branch will be downloaded to my PC?
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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...
How to correctly implement custom iterators and const_iterators?
...e, std::iterator with random_access_iterator_tag.These base classes define all type definitions required by STL and do other work.
To avoid code duplication iterator class should be a template class and be parametrized by "value type", "pointer type", "reference type" or all of them (depends on impl...
What happens when there's insufficient memory to throw an OutOfMemoryError?
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The JVM never really runs out of memory. It does memory computation of the heap stack in advance.
The Structure of the JVM, Chapter 3, section 3.5.2 states:
If Java virtual machine stacks can be dynamically expanded, and expansion is...
What is the difference between “text” and new String(“text”)?
... a reference to an instance of class String, and is derived from a CONSTANT_String_info structure (§4.4.3) in the binary representation of a class or interface. The CONSTANT_String_info structure gives the sequence of Unicode code points constituting the string literal.
The Java programming la...
How can I export tables to Excel from a webpage [closed]
... can I export tables to Excel from a webpage. I want the export to contain all the formatting and colours.
14 Answers
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