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Odd behavior when Java converts int to byte?
...+ unsignedByte);
Would print out: "Signed: -1 Unsigned: 255"
What's actually happening here?
We are using bitwise AND to mask all of the extraneous sign bits (the 1's to the left of the least significant 8 bits.)
When an int is converted into a byte, Java chops-off the left-most 24 bits
111111...
What is the list of possible values for navigator.platform as of today? [closed]
...urate.
The definition
As far as I know there isn't a single public list of all possible `navigator.platform` values, even though the property has been around for quite a bit. To make things worse, the property's definition changed throughout the years. It used to be:
navigator.platform indicates th...
Execution time of C program
I have a C program that aims to be run in parallel on several processors. I need to be able to record the execution time (which could be anywhere from 1 second to several minutes). I have searched for answers, but they all seem to suggest using the clock() function, which then involves calculating...
How to deal with SettingWithCopyWarning in Pandas?
...
The SettingWithCopyWarning was created to flag potentially confusing "chained" assignments, such as the following, which does not always work as expected, particularly when the first selection returns a copy. [see GH5390 and GH5597 for background discussion.]
df[df['A'] > 2...
Hidden features of C
I know there is a standard behind all C compiler implementations, so there should be no hidden features. Despite that, I am sure all C developers have hidden/secret tricks they use all the time.
...
How do I use raw_input in Python 3
...
There was originally a function input() which acted something like the current eval(input()). It was a leftover from when Python was less security conscious. The change simplified the language. See also "import this" for a deeper explanat...
Why do we always prefer using parameters in SQL statements?
...uld be
SELECT empSalary from employee where salary = 0 or 1=1
whereby all empSalaries would be returned.
Further, a user could perform far worse commands against your database, including deleting it If they wrote 0; Drop Table employee:
SELECT empSalary from employee where salary = 0; Drop Ta...
What is the purpose of Flask's context stacks?
...backend". In other words, the Flask(...) application constructor has been called twice, creating two instances of a Flask application.
Contexts
When you are working with Flask, you often end up using global variables to access various functionality. For example, you probably have code that reads.....
Nested classes' scope?
...e will use that object the next time it is executed.)
If you instead want all Inner objects to have a reference to an Outer because outer_var is really an instance attribute:
class Outer(object):
def __init__(self):
self.outer_var = 1
def get_inner(self):
return self.Inner...
Can I install Python windows packages into virtualenvs?
Virtualenv is great: it lets me keep a number of distinct Python installations so that different projects' dependencies aren't all thrown together into a common pile.
...