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//! //! This crate provides a library for performing automatic differentiation. //! //! # Examples //! //! The following example differentiates a 1D function defined by a closure. //! //! ```rust //! # use autodiff::*; //! # fn main() { //! // Define a function `f(x) = e^{-0.5*x^2}` //! let f = |x: F| (-x * x / F::cst(2.0)).exp(); //! //! // Differentiate `f` at zero. //! println!("{}", diff(f, 0.0)); // prints `0` //! # assert_eq!(diff(f, 0.0), 0.0); //! # } //! ``` //! //! To compute the gradient of a function, use the function `grad` as follows: //! //! ```rust //! # use autodiff::*; //! # fn main() { //! // Define a function `f(x,y) = x*y^2` //! let f = |x: &[F]| x[0] * x[1] * x[1]; //! //! // Differentiate `f` at `(1,2)`. //! let g = grad(f, &vec![1.0, 2.0]); //! println!("({}, {})", g[0], g[1]); // prints `(4, 4)` //! # assert_eq!(g, vec![4.0, 4.0]); //! # } //! ``` //! //! Compute a specific derivative of a multi-variable function: //! //! ```rust //! # use autodiff::*; //! # fn main() { //! // Define a function `f(x,y) = x*y^2`. //! let f = |v: &[F]| v[0] * v[1] * v[1]; //! //! // Differentiate `f` at `(1,2)` with respect to `x` (the first unknown) only. //! let v = vec![ //! F::var(1.0), // Create a variable. //! F::cst(2.0), // Create a constant. //! ]; //! println!("{}", f(&v).deriv()); // prints `4` //! # assert_eq!(f(&v).deriv(), 4.0); //! # } //! ``` #[cfg(feature = "cgmath")] pub mod cgmath; pub mod forward_autodiff; #[cfg(feature = "cgmath")] pub use crate::cgmath::*; pub use forward_autodiff::*; // Re-export useful traits for performing computations. pub use num_traits::{Float, FloatConst, NumCast, One, ToPrimitive, Zero};