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Reading an Excel file in python using pandas
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Close: first you call ExcelFile, but then you call the .parse method and pass it the sheet name.
>>> xl = pd.ExcelFile("dummydata.xlsx")
>>> xl.sheet_names
[u'Sheet1', u'Sheet2', u'Sheet3']
>>> df = xl.parse("Sheet...
Is there a performance difference between i++ and ++i in C++?
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However, if i is an instance of a C++ class, then i++ and ++i are making calls to one of the operator++ functions. Here's a standard pair of these functions:
Foo& Foo::operator++() // called for ++i
{
this->data += 1;
return *this;
}
Foo Foo::operator++(int ignored_dummy_value) ...
What is meant with “const” at end of function declaration? [duplicate]
...) results in a function like int Foo_Bar(Foo* this, int random_arg), and a call such as Foo f; f.Bar(4) will internally correspond to something like Foo f; Foo_Bar(&f, 4). Now adding the const at the end (int Foo::Bar(int random_arg) const) can then be understood as a declaration with a const th...
How to know what the 'errno' means?
When calling execl(...) , I get an errno=2 . What does it mean? How can I know the meaning of this errno ?
15 Answers
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How can I disable logging of asset pipeline (sprockets) messages in Ruby on Rails 3.1?
...ger=, Logger.new('/dev/null'))
Rails::Rack::Logger.class_eval do
def call_with_quiet_assets(env)
previous_level = Rails.logger.level
Rails.logger.level = Logger::ERROR if env['PATH_INFO'] =~ %r{^/assets/}
call_without_quiet_assets(env)
ensure
Rails.logger.level = pr...
Bootstrap carousel multiple frames at once
...ted 2019...
Bootstrap 4
The carousel has changed in 4.x, and the multi-slide animation transitions can be overridden like this...
.carousel-inner .carousel-item-right.active,
.carousel-inner .carousel-item-next {
transform: translateX(33.33%);
}
.carousel-inner .carousel-item-left.active,
.ca...
How do I create a simple 'Hello World' module in Magento?
...ndexAction(){
echo "We're echoing just to show that this is what's called, normally you'd have some kind of redirect going on here";
}
}
What we've just setup is the module/frontName controller.
This is the default controller and the default action of the module.
If you want to add co...
How do I create a nice-looking DMG for Mac OS X using command-line tools?
...wk '{print $1}')
Store the background picture (in PNG format) in a folder called ".background" in the DMG, and store its name in the "backgroundPictureName" variable.
Use AppleScript to set the visual styles (name of .app must be in bash variable "applicationName", use variables for the other prop...
Get properties and values from unknown object
...nts the type (at runtime) of the instance in the list. You can do this by calling the GetType method on Object. Because it is on the Object class, it's callable by every object in .NET, as all types derive from Object (well, technically, not everything, but that's not important here).
Once you ha...
What is the difference between exit(0) and exit(1) in C?
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@CatPlusPlus: On OpenVMS, calling exit with any odd value denotes success. exit(0) is treated as a special case for the sake of C conformance. Yes, POSIX is a standard, but not all systems conform to it. If you want to write code that assumes POSIX, y...