Expression-class function

The Expression class.

This class represents a mathematical expression. class

## S4 method for signature 'Expression'
value(object)

## S4 method for signature 'Expression'
grad(object)

## S4 method for signature 'Expression'
domain(object)

## S4 method for signature 'Expression'
as.character(x)

## S4 method for signature 'Expression'
name(x)

## S4 method for signature 'Expression'
expr(object)

## S4 method for signature 'Expression'
is_constant(object)

## S4 method for signature 'Expression'
is_affine(object)

## S4 method for signature 'Expression'
is_convex(object)

## S4 method for signature 'Expression'
is_concave(object)

## S4 method for signature 'Expression'
is_dcp(object)

## S4 method for signature 'Expression'
is_log_log_constant(object)

## S4 method for signature 'Expression'
is_log_log_affine(object)

## S4 method for signature 'Expression'
is_log_log_convex(object)

## S4 method for signature 'Expression'
is_log_log_concave(object)

## S4 method for signature 'Expression'
is_dgp(object)

## S4 method for signature 'Expression'
is_hermitian(object)

## S4 method for signature 'Expression'
is_psd(object)

## S4 method for signature 'Expression'
is_nsd(object)

## S4 method for signature 'Expression'
is_quadratic(object)

## S4 method for signature 'Expression'
is_symmetric(object)

## S4 method for signature 'Expression'
is_pwl(object)

## S4 method for signature 'Expression'
is_qpwa(object)

## S4 method for signature 'Expression'
is_zero(object)

## S4 method for signature 'Expression'
is_nonneg(object)

## S4 method for signature 'Expression'
is_nonpos(object)

## S4 method for signature 'Expression'
dim(x)

## S4 method for signature 'Expression'
is_real(object)

## S4 method for signature 'Expression'
is_imag(object)

## S4 method for signature 'Expression'
is_complex(object)

## S4 method for signature 'Expression'
size(object)

## S4 method for signature 'Expression'
ndim(object)

## S4 method for signature 'Expression'
flatten(object)

## S4 method for signature 'Expression'
is_scalar(object)

## S4 method for signature 'Expression'
is_vector(object)

## S4 method for signature 'Expression'
is_matrix(object)

## S4 method for signature 'Expression'
nrow(x)

## S4 method for signature 'Expression'
ncol(x)

Arguments

• x, object: An Expression object.

Methods (by generic)

• value(Expression): The value of the expression.
• grad(Expression): The (sub/super)-gradient of the expression with respect to each variable.
• domain(Expression): A list of constraints describing the closure of the region where the expression is finite.
• as.character(Expression): The string representation of the expression.
• name(Expression): The name of the expression.
• expr(Expression): The expression itself.
• is_constant(Expression): The expression is constant if it contains no variables or is identically zero.
• is_affine(Expression): The expression is affine if it is constant or both convex and concave.
• is_convex(Expression): A logical value indicating whether the expression is convex.
• is_concave(Expression): A logical value indicating whether the expression is concave.
• is_dcp(Expression): The expression is DCP if it is convex or concave.
• is_log_log_constant(Expression): Is the expression log-log constant, i.e., elementwise positive?
• is_log_log_affine(Expression): Is the expression log-log affine?
• is_log_log_convex(Expression): Is the expression log-log convex?
• is_log_log_concave(Expression): Is the expression log-log concave?
• is_dgp(Expression): The expression is DGP if it is log-log DCP.
• is_hermitian(Expression): A logical value indicating whether the expression is a Hermitian matrix.
• is_psd(Expression): A logical value indicating whether the expression is a positive semidefinite matrix.
• is_nsd(Expression): A logical value indicating whether the expression is a negative semidefinite matrix.
• is_quadratic(Expression): A logical value indicating whether the expression is quadratic.
• is_symmetric(Expression): A logical value indicating whether the expression is symmetric.
• is_pwl(Expression): A logical value indicating whether the expression is piecewise linear.
• is_qpwa(Expression): A logical value indicating whether the expression is quadratic of piecewise affine.
• is_zero(Expression): The expression is zero if it is both nonnegative and nonpositive.
• is_nonneg(Expression): A logical value indicating whether the expression is nonnegative.
• is_nonpos(Expression): A logical value indicating whether the expression is nonpositive.
• dim(Expression): The c(row, col) dimensions of the expression.
• is_real(Expression): A logical value indicating whether the expression is real.
• is_imag(Expression): A logical value indicating whether the expression is imaginary.
• is_complex(Expression): A logical value indicating whether the expression is complex.
• size(Expression): The number of entries in the expression.
• ndim(Expression): The number of dimensions of the expression.
• flatten(Expression): Vectorizes the expression.
• is_scalar(Expression): A logical value indicating whether the expression is a scalar.
• is_vector(Expression): A logical value indicating whether the expression is a row or column vector.
• is_matrix(Expression): A logical value indicating whether the expression is a matrix.
• nrow(Expression): Number of rows in the expression.
• ncol(Expression): Number of columns in the expression.