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Deep copying an NSArray
...ple documentation about deep copies explicitly states:
If you only need a one-level-deep copy:
NSMutableArray *newArray = [[NSMutableArray alloc]
initWithArray:oldArray copyItems:YES];
The above code creates a new array whose members are shallow copies of the members...
When is JavaScript's eval() not evil?
...ll compute the result during the parse rather than run another parser (the one inside eval()). But it may be easier to code using eval(), and the performance hit will probably be unnoticeable. It looks like eval() in this case is no more evil than any other function that could possibly save you some...
Why does std::getline() skip input after a formatted extraction?
...ty of your program, it follows that it must be skipped or ignored somehow. One option is to call std::cin.ignore() after the the first extraction. It will discard the next available character so that the newline is no longer in the way.
std::getline(std::cin.ignore(), state)
In-Depth Explanation:
...
What does asterisk * mean in Python? [duplicate]
...ng to a new
empty dictionary.
Also, see Function Calls.
Assuming that one knows what positional and keyword arguments are, here are some examples:
Example 1:
# Excess keyword argument (python 2) example:
def foo(a, b, c, **args):
print "a = %s" % (a,)
print "b = %s" % (b,)
print "...
How do Trigonometric functions work?
...cipes.
edit: Wikipedia has a semi-decent article on approximation theory. One of the sources they cite (Hart, "Computer Approximations") is out of print (& used copies tend to be expensive) but goes into a lot of detail about stuff like this. (Jack Ganssle mentions this in issue 39 of his newsl...
How do I daemonize an arbitrary script in unix?
...standard error to a different file of your choice. If you want to use just one file for both standard out and standard error you can us this:
nohup yourScript.sh script args >script.out 2>&1 &
The 2>&1 tells the shell to redirect standard error (file descriptor 2) to the same...
Element-wise addition of 2 lists?
...e python syntax is really elegant and simple, but unfortunately this isn't one of them. And for such a simple task, it's a pity.... Why would they make "+" concatenate the lists when there's already the .extend() method?
– Nic Scozzaro
Nov 13 '18 at 2:37
...
Why are const parameters not allowed in C#?
...rt of feature into any hypothetical future version of C#, if there even is one, which we have not announced one way or the other. It is something I would love to see, and something which the coming emphasis on multi-core computing might require, but none of this should be in any way construed to be ...
How can I inject a property value into a Spring Bean which was configured using annotations?
...
systemProperties is an implicit object and strategyBean is a bean name.
One more example, which works when you want to grab a property from a Properties object. It also shows that you can apply @Value to fields:
@Value("#{myProperties['github.oauth.clientId']}")
private String githubOauthClientI...
如何选择机器学习算法 - 大数据 & AI - 清泛网移动版 - 专注IT技能提升
...eally care about accuracy, your best bet is to test out a couple different ones (making sure to try different parameters within each algorithm as well), and select the best one by cross-validation. But if you’re simply looking for a “good enough” algorithm for your problem, or a place to s...