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Is pass-by-value a reasonable default in C++11?
In traditional C++, passing by value into functions and methods is slow for large objects, and is generally frowned upon. Instead, C++ programmers tend to pass references around, which is faster, but which introduces all sorts of complicated questions around ownership and especially around memory ma...
Objective-C declared @property attributes (nonatomic, copy, strong, weak)
...ail when I must use each attribute: nonatomic , copy , strong , weak , and so on, for a declared property, and explain what each does? Some sort of example would be great also. I am using ARC.
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Fitting empirical distribution to theoretical ones with Scipy (Python)?
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Distribution Fitting with Sum of Square Error (SSE)
This is an update and modification to Saullo's answer, that uses the full list of the current scipy.stats distributions and returns the distribution with the least SSE between the distribution's histogram and the data's histogram.
Example Fit...
Speed up the loop operation in R
... over a data.frame object. It simply adds a new column to a data.frame and accumulates something. (simple operation). The data.frame has roughly 850K rows. My PC is still working (about 10h now) and I have no idea about the runtime.
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When splitting an empty string in Python, why does split() return an empty list while split('\n') re
I am using split('\n') to get lines in one string, and found that ''.split() returns an empty list, [] , while ''.split('\n') returns [''] . Is there any specific reason for such a difference?
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Why is it bad style to `rescue Exception => e` in Ruby?
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TL;DR: Use StandardError instead for general exception catching. When the original exception is re-raised (e.g. when rescuing to log the exception only), rescuing Exception is probably okay.
Exception is the root of Ruby's exception hi...
How do I catch a numpy warning like it's an exception (not just for testing)?
...rr(all='warn'), which will transform the printed warning in a real warning and you'll be able to use the above solution to localize this change in behaviour.
Once you actually have a warning, you can use the warnings module to control how the warnings should be treated:
>>> import warnin...
What is the difference between Serializable and Externalizable in Java?
What is the difference between Serializable and Externalizable in Java?
11 Answers
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Pros and cons of AppSettings vs applicationSettings (.NET app.config / Web.config)
...r to deal with - just slap in a <add key="...." value="..." /> entry and you're done.
The downside is: there's no type-checking, e.g. you cannot safely assume your number that you wanted to configure there really is a number - someone could put a string into that setting..... you just access ...
Uses for Optional
...eem to swing between wanting to use it everywhere something may be null , and nowhere at all.
14 Answers
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