In the documentation of Swift the type of "Double" is "alias Double", but that doesn't make much sense (you don't mean an alias of Double?).
So, what is the type of "Double"?
it's "unbounded floating-point type", so it's Double in Swift, though it's called an Alias.
It sounds like you're used to C++. Alias is the "C++ way of saying wrapper", and what's the "Swift way".
Basically it's a type that wraps a floating point value, much like the C++ type long double. Only it is always 64 bit large.
The present disclosure relates to an operation unit and a system that are provided with a display panel that can display touch information such as a touch operation or a position coordinate of a pointer, and with a liquid crystal display device that displays an image on a display panel.
A mobile phone and a mobile information terminal that perform a touch operation on a display screen, and a touch panel used for such a mobile phone and a mobile information terminal are known. A known touch panel includes a touch detection element that is incorporated in a display device, such as a liquid crystal display device or a plasma display device, which displays an image (e.g., see Japanese Patent Application Laid-open Publication No. H7-23834).
In a liquid crystal display device, one or a plurality of pixels are arranged in a display device, and an image is displayed by controlling the amount of transmission of light emitted from the light-emitting elements of each pixel.
In recent years, in order to improve the operational responsiveness of a touch panel or reduce the size and weight of the touch panel, a display device that detects a touch operation by detecting the position of a pointer (finger or stylus) that is brought into contact with the display surface of the display device by using a sensing device, such as a pressure sensor, is proposed. 0b46394aab