Package edu.wpi.first.units

Interface UnaryFunction

Functional Interface:
This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.
@FunctionalInterface public interface UnaryFunction
A function that accepts a single double and returns a double result. This is used to represent arbitrary mapping functions for converting units to and from a base unit representation. Temperature units, in particular, typically have an offset from a value in Kelvin and may have a multiplication factor added in, which means that units cannot always be represented as simple ratios of their base units.

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final UnaryFunction
    IDENTITY
    The identity function that simply returns the input value.

  • Method Summary

    Modifier and Type
    Method
    Description
    double
    apply(double input)
    Applies this function to the input value and returns the result.
    default UnaryFunction
    div(double divisor)
    Creates a composite function h(x) such that h(x) = 1/k * f(x).
    default UnaryFunction
    div(UnaryFunction divisor)
    Creates a composite function h(x) such that h(x) = f(x) / g(x).
    default UnaryFunction
    exp(double exponent)
    Creates a composite function h(x) such that h(x) = f(x) ^ k.
    default UnaryFunction
    exp(UnaryFunction exponent)
    Creates a composite function h(x) such that h(x) = f(x) ^ g(x).
    default UnaryFunction
    mult(double multiplier)
    Creates a composite function h(x) such that h(x) = k * f(x).
    default UnaryFunction
    mult(UnaryFunction multiplier)
    Creates a composite function h(x) such that h(x) = f(x) * g(x).
    default UnaryFunction
    pipeTo(UnaryFunction next)
    Constructs a new function that first calls this function, then passes the result to another as input.

  • Field Details

    • IDENTITY

      static final UnaryFunction IDENTITY
      The identity function that simply returns the input value.

  • Method Details

    • apply

      double apply(double input)
      Applies this function to the input value and returns the result.
      Parameters:
      input - the input value to the function
      Returns:
      the result

    • pipeTo

      default UnaryFunction pipeTo(UnaryFunction next)
      Constructs a new function that first calls this function, then passes the result to another as input. 
       f = x -> x + 1 // f(x) = x + 1
 g = x -> 2 * x // g(x) = 2x

 h = f.pipeTo(g) // h(x) = g(f(x))
      Parameters:
      next - the next operation to pipe to
      Returns:
      the composite function g(f(x))

    • mult

      default UnaryFunction mult(UnaryFunction multiplier)
      Creates a composite function h(x) such that h(x) = f(x) * g(x).
      Parameters:
      multiplier - the function to multiply this one by
      Returns:
      the composite function f(x) * g(x)

    • mult

      default UnaryFunction mult(double multiplier)
      Creates a composite function h(x) such that h(x) = k * f(x).
      Parameters:
      multiplier - the constant value to multiply this function's results by
      Returns:
      the composite function k * f(x)

    • div

      default UnaryFunction div(UnaryFunction divisor)
      Creates a composite function h(x) such that h(x) = f(x) / g(x).
      Parameters:
      divisor - the function to divide this one by
      Returns:
      the composite function f(x) / g(x)

    • div

      default UnaryFunction div(double divisor)
      Creates a composite function h(x) such that h(x) = 1/k * f(x).
      Parameters:
      divisor - the constant value to divide this function's results by
      Returns:
      the composite function 1/k * f(x)

    • exp

      default UnaryFunction exp(UnaryFunction exponent)
      Creates a composite function h(x) such that h(x) = f(x) ^ g(x).
      Parameters:
      exponent - the function to exponentiate this function's results by
      Returns:
      the composite function f(x) ^ g(x)

    • exp

      default UnaryFunction exp(double exponent)
      Creates a composite function h(x) such that h(x) = f(x) ^ k.
      Parameters:
      exponent - the constant value to exponentiate this function's results by
      Returns:
      the composite function f(x) ^ k