Learn R Programming
CVXR (version 1.0)

Expression-class: The Expression class.

Description

This class represents a mathematical expression.

Usage

# S4 method for Expression
value(object)
# S4 method for Expression
grad(object)
# S4 method for Expression
domain(object)
# S4 method for Expression
as.character(x)
# S4 method for Expression
name(x)
# S4 method for Expression
expr(object)
# S4 method for Expression
is_constant(object)
# S4 method for Expression
is_affine(object)
# S4 method for Expression
is_convex(object)
# S4 method for Expression
is_concave(object)
# S4 method for Expression
is_dcp(object)
# S4 method for Expression
is_log_log_constant(object)
# S4 method for Expression
is_log_log_affine(object)
# S4 method for Expression
is_log_log_convex(object)
# S4 method for Expression
is_log_log_concave(object)
# S4 method for Expression
is_dgp(object)
# S4 method for Expression
is_hermitian(object)
# S4 method for Expression
is_psd(object)
# S4 method for Expression
is_nsd(object)
# S4 method for Expression
is_quadratic(object)
# S4 method for Expression
is_symmetric(object)
# S4 method for Expression
is_pwl(object)
# S4 method for Expression
is_qpwa(object)
# S4 method for Expression
is_zero(object)
# S4 method for Expression
is_nonneg(object)
# S4 method for Expression
is_nonpos(object)
# S4 method for Expression
dim(x)
# S4 method for Expression
is_real(object)
# S4 method for Expression
is_imag(object)
# S4 method for Expression
is_complex(object)
# S4 method for Expression
size(object)
# S4 method for Expression
ndim(object)
# S4 method for Expression
flatten(object)
# S4 method for Expression
is_scalar(object)
# S4 method for Expression
is_vector(object)
# S4 method for Expression
is_matrix(object)
# S4 method for Expression
nrow(x)
# S4 method for Expression
ncol(x)

Arguments

x, object

An '>Expression object.

Methods (by generic)

  • value: The value of the expression.

  • grad: The (sub/super)-gradient of the expression with respect to each variable.

  • domain: A list of constraints describing the closure of the region where the expression is finite.

  • as.character: The string representation of the expression.

  • name: The name of the expression.

  • expr: The expression itself.

  • is_constant: The expression is constant if it contains no variables or is identically zero.

  • is_affine: The expression is affine if it is constant or both convex and concave.

  • is_convex: A logical value indicating whether the expression is convex.

  • is_concave: A logical value indicating whether the expression is concave.

  • is_dcp: The expression is DCP if it is convex or concave.

  • is_log_log_constant: Is the expression log-log constant, i.e., elementwise positive?

  • is_log_log_affine: Is the expression log-log affine?

  • is_log_log_convex: Is the expression log-log convex?

  • is_log_log_concave: Is the expression log-log concave?

  • is_dgp: The expression is DGP if it is log-log DCP.

  • is_hermitian: A logical value indicating whether the expression is a Hermitian matrix.

  • is_psd: A logical value indicating whether the expression is a positive semidefinite matrix.

  • is_nsd: A logical value indicating whether the expression is a negative semidefinite matrix.

  • is_quadratic: A logical value indicating whether the expression is quadratic.

  • is_symmetric: A logical value indicating whether the expression is symmetric.

  • is_pwl: A logical value indicating whether the expression is piecewise linear.

  • is_qpwa: A logical value indicating whether the expression is quadratic of piecewise affine.

  • is_zero: The expression is zero if it is both nonnegative and nonpositive.

  • is_nonneg: A logical value indicating whether the expression is nonnegative.

  • is_nonpos: A logical value indicating whether the expression is nonpositive.

  • dim: The c(row, col) dimensions of the expression.

  • is_real: A logical value indicating whether the expression is real.

  • is_imag: A logical value indicating whether the expression is imaginary.

  • is_complex: A logical value indicating whether the expression is complex.

  • size: The number of entries in the expression.

  • ndim: The number of dimensions of the expression.

  • flatten: Vectorizes the expression.

  • is_scalar: A logical value indicating whether the expression is a scalar.

  • is_vector: A logical value indicating whether the expression is a row or column vector.

  • is_matrix: A logical value indicating whether the expression is a matrix.

  • nrow: Number of rows in the expression.

  • ncol: Number of columns in the expression.