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Why is “int i = 2147483647 + 1;” OK, but “byte b = 127 + 1;” is not compilable?
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Constants are evaluated as ints, so 2147483647 + 1 overflows and gives you a new int, which is assignable to int, while 127 + 1 also evaluated as int equals to 128, and it is not assignable to byte.
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Linear Regression and group by in R
...ction. My data is an annual time series with one field for year (22 years) and another for state (50 states). I want to fit a regression for each state so that at the end I have a vector of lm responses. I can imagine doing for loop for each state then doing the regression inside the loop and adding...
jQuery's jquery-1.10.2.min.map is triggering a 404 (Not Found)
...get the files
Next, it's an easy fix. Head to http://jquery.com/download/ and click the Download the map file link for your version, and you'll want the uncompressed file downloaded as well.
Having the map file in place allows you do debug your minified jQuery via the original sources, which wil...
Null vs. False vs. 0 in PHP
...m told that good developers can spot/utilize the difference between Null and False and 0 and all the other good "nothing" entities.
What is the difference, specifically in PHP? Does it have something to do with === ?
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What is the difference between a port and a socket?
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Summary
A TCP socket is an endpoint instance defined by an IP address and a port in the context of either a particular TCP connection or the listening state.
A port is a virtualisation identifier defining a service endpoint (as distinct from a service instance endpoint aka session identifier)...
Can C++ code be valid in both C++03 and C++11 but do different things?
Is it possible for C++ code to conform to both the C++03 standard and the C++11 standard, but do different things depending on under which standard it is being compiled?
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How to install packages offline?
What's the best way to download a python package and it's dependencies from pypi for offline installation on another machine? Is there any easy way to do this with pip or easy_install? I'm trying to install the requests library on a FreeBSD box that is not connected to the internet.
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How to do a FULL OUTER JOIN in MySQL?
...oducing duplicate rows by using an anti-join pattern for the second query, and then use a UNION ALL set operator to combine the two sets. In the more general case, where a FULL OUTER JOIN would return duplicate rows, we can do this:
SELECT * FROM t1
LEFT JOIN t2 ON t1.id = t2.id
UNION ALL
SELECT * ...
What is the difference between shallow copy, deepcopy and normal assignment operation?
...wards the existing object. The docs explain the difference between shallow and deep copies:
The difference between shallow and deep copying is only relevant for
compound objects (objects that contain other objects, like lists or
class instances):
A shallow copy constructs a new compo...
Waiting until two async blocks are executed before starting another block
When using GCD, we want to wait until two async blocks are executed and done before moving on to the next steps of execution. What is the best way to do that?
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