Struct DirectionalDerivatives 

pub struct DirectionalDerivatives;

Directional derivative operations

Implementations

impl DirectionalDerivatives

pub fn compute( expr: &Expression, variables: Vec<Symbol>, direction: Vec<Expression>, ) -> Expression

Compute directional derivative

Examples

use mathhook_core::simplify::Simplify;
use mathhook_core::{Expression};
use mathhook_core::symbol;
use mathhook_core::calculus::derivatives::DirectionalDerivatives;

let x = symbol!(x);
let y = symbol!(y);
let expr = Expression::add(vec![
    Expression::pow(Expression::symbol(x.clone()), Expression::integer(2)),
    Expression::pow(Expression::symbol(y.clone()), Expression::integer(2))
]);
let direction = vec![Expression::integer(1), Expression::integer(1)];
let dir_deriv = DirectionalDerivatives::compute(&expr, vec![x, y], direction);

pub fn unit_directional( expr: &Expression, variables: Vec<Symbol>, direction: Vec<Expression>, ) -> Expression

Compute unit directional derivative (normalizes direction vector)

Examples

use mathhook_core::{Expression, Symbol};
use mathhook_core::symbol;
use mathhook_core::calculus::derivatives::DirectionalDerivatives;

let x = symbol!(x);
let y = symbol!(y);
let expr = Expression::add(vec![
    Expression::pow(Expression::symbol(x.clone()), Expression::integer(2)),
    Expression::pow(Expression::symbol(y.clone()), Expression::integer(2))
]);
let direction = vec![Expression::integer(3), Expression::integer(4)];
let unit_dir_deriv = DirectionalDerivatives::unit_directional(&expr, vec![x, y], direction);