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//! Specialized expression constructors for complex, matrix, set, and advanced types
use crate::core::expression::{ComplexData, Expression, IntervalData, PiecewiseData};
use std::sync::Arc;
impl Expression {
/// Create a complex number expression
///
/// # Examples
///
/// ```rust
/// use mathhook_core::Expression;
///
/// let expr = Expression::complex(
/// Expression::integer(3),
/// Expression::integer(4),
/// );
/// ```
pub fn complex(real: Expression, imag: Expression) -> Self {
Self::Complex(Arc::new(ComplexData { real, imag }))
}
/// Create a set expression
///
/// # Examples
///
/// ```rust
/// use mathhook_core::Expression;
///
/// let set = Expression::set(vec![
/// Expression::integer(1),
/// Expression::integer(2),
/// Expression::integer(3),
/// ]);
/// ```
pub fn set(elements: Vec<Expression>) -> Self {
Self::Set(Arc::new(elements))
}
/// Create an interval expression
///
/// # Examples
///
/// ```rust
/// use mathhook_core::Expression;
///
/// let interval = Expression::interval(
/// Expression::integer(0),
/// Expression::integer(10),
/// true,
/// false,
/// );
/// ```
pub fn interval(
start: Expression,
end: Expression,
start_inclusive: bool,
end_inclusive: bool,
) -> Self {
Self::Interval(Arc::new(IntervalData {
start,
end,
start_inclusive,
end_inclusive,
}))
}
/// Create a piecewise function expression
///
/// # Examples
///
/// ```rust
/// use mathhook_core::{Expression, symbol};
///
/// let piecewise = Expression::piecewise(
/// vec![(Expression::symbol(symbol!(x)), Expression::integer(1))],
/// Some(Expression::integer(0)),
/// );
/// ```
pub fn piecewise(pieces: Vec<(Expression, Expression)>, default: Option<Expression>) -> Self {
Self::Piecewise(Arc::new(PiecewiseData { pieces, default }))
}
/// Create a matrix expression from rows
///
/// # Examples
///
/// ```rust
/// use mathhook_core::Expression;
///
/// let matrix = Expression::matrix(vec![
/// vec![Expression::integer(1), Expression::integer(2)],
/// vec![Expression::integer(3), Expression::integer(4)]
/// ]);
/// ```
pub fn matrix(rows: Vec<Vec<Expression>>) -> Self {
use crate::matrices::Matrix;
Self::Matrix(Arc::new(Matrix::dense(rows)))
}
/// Create an identity matrix expression
///
/// # Examples
///
/// ```rust
/// use mathhook_core::Expression;
/// use mathhook_core::matrices::operations::MatrixOperations;
///
/// let identity = Expression::identity_matrix(3);
/// assert!(identity.is_identity_matrix());
/// ```
pub fn identity_matrix(size: usize) -> Self {
use crate::matrices::Matrix;
Self::Matrix(Arc::new(Matrix::identity(size)))
}
/// Create a method call expression
///
/// # Examples
///
/// ```rust
/// use mathhook_core::{Expression, symbol};
///
/// let matrix = Expression::symbol(symbol!(A));
/// let det_call = Expression::method_call(matrix, "det", vec![]);
/// let trace_call = Expression::method_call(
/// Expression::symbol(symbol!(B)),
/// "trace",
/// vec![]
/// );
/// ```
pub fn method_call(
object: Expression,
method_name: impl Into<String>,
args: Vec<Expression>,
) -> Self {
use crate::core::expression::MethodCallData;
Self::MethodCall(Arc::new(MethodCallData {
object,
method_name: method_name.into(),
args,
}))
}
/// Create a zero matrix expression
///
/// # Examples
///
/// ```rust
/// use mathhook_core::matrices::operations::MatrixOperations;
/// use mathhook_core::Expression;
///
/// let zero = Expression::zero_matrix(2, 3);
/// assert!(zero.is_zero_matrix());
/// ```
pub fn zero_matrix(rows: usize, cols: usize) -> Self {
use crate::matrices::Matrix;
Self::Matrix(Arc::new(Matrix::zero(rows, cols)))
}
/// Create a diagonal matrix expression
///
/// # Examples
///
/// ```rust
/// use mathhook_core::Expression;
///
/// let diag = Expression::diagonal_matrix(vec![
/// Expression::integer(1),
/// Expression::integer(2),
/// Expression::integer(3)
/// ]);
/// ```
pub fn diagonal_matrix(diagonal_elements: Vec<Expression>) -> Self {
use crate::matrices::Matrix;
Self::Matrix(Arc::new(Matrix::diagonal(diagonal_elements)))
}
/// Create a scalar matrix expression (c*I)
///
/// # Examples
///
/// ```rust
/// use mathhook_core::Expression;
///
/// let scalar = Expression::scalar_matrix(3, Expression::integer(5));
/// // Creates 5*I (5 times the 3x3 identity matrix)
/// ```
pub fn scalar_matrix(size: usize, scalar_value: Expression) -> Self {
use crate::matrices::Matrix;
Self::Matrix(Arc::new(Matrix::scalar(size, scalar_value)))
}
/// Create matrix from nested arrays (convenience method)
///
/// # Examples
///
/// ```rust
/// use mathhook_core::Expression;
///
/// let matrix = Expression::matrix_from_arrays([
/// [1, 2, 3],
/// [4, 5, 6]
/// ]);
/// ```
pub fn matrix_from_arrays<const R: usize, const C: usize>(arrays: [[i64; C]; R]) -> Self {
use crate::matrices::Matrix;
Self::Matrix(Arc::new(Matrix::from_arrays(arrays)))
}
/// Create a commutator: [A, B] = AB - BA
///
/// The commutator measures the failure of two operators to commute.
/// It is zero for commutative operators and nonzero for noncommutative.
///
/// # Examples
///
/// ```rust
/// use mathhook_core::{Expression, symbol};
///
/// let A = Expression::symbol(symbol!(A; matrix));
/// let B = Expression::symbol(symbol!(B; matrix));
/// let comm = Expression::commutator(A.clone(), B.clone());
/// // Represents: AB - BA
/// ```
///
/// # Mathematical Properties
///
/// - [A, B] = -[B, A] (antisymmetry)
/// - [A, A] = 0 (self-commutator is zero)
/// - Jacobi identity: [A, [B, C]] + [B, [C, A]] + [C, [A, B]] = 0
///
/// # Quantum Mechanics Example
///
/// ```rust
/// use mathhook_core::{Expression, symbol};
///
/// let x = Expression::symbol(symbol!(x; operator));
/// let p = Expression::symbol(symbol!(p; operator));
/// let comm = Expression::commutator(x, p);
/// // In quantum mechanics: [x, p] = ih (canonical commutation relation)
/// ```
pub fn commutator(a: Expression, b: Expression) -> Self {
Self::add(vec![
Self::mul(vec![a.clone(), b.clone()]),
Self::mul(vec![Self::integer(-1), Self::mul(vec![b, a])]),
])
}
/// Create an anticommutator: {A, B} = AB + BA
///
/// The anticommutator is the symmetric combination of two operators.
///
/// # Examples
///
/// ```rust
/// use mathhook_core::{Expression, symbol};
///
/// let A = Expression::symbol(symbol!(A; matrix));
/// let B = Expression::symbol(symbol!(B; matrix));
/// let anticomm = Expression::anticommutator(A.clone(), B.clone());
/// // Represents: AB + BA
/// ```
///
/// # Mathematical Properties
///
/// - {A, B} = {B, A} (symmetry)
/// - {A, A} = 2A^2 (self-anticommutator)
///
/// # Physics Example
///
/// ```rust
/// use mathhook_core::{Expression, symbol};
///
/// let sigma_x = Expression::symbol(symbol!(sigma_x; operator));
/// let sigma_y = Expression::symbol(symbol!(sigma_y; operator));
/// let anticomm = Expression::anticommutator(sigma_x, sigma_y);
/// // For Pauli matrices: {sigma_x, sigma_y} = 0
/// ```
pub fn anticommutator(a: Expression, b: Expression) -> Self {
Self::add(vec![
Self::mul(vec![a.clone(), b.clone()]),
Self::mul(vec![b, a]),
])
}
}