prune

Overloads

Name	Description
prune(ComplexOperatorSum input) -> ComplexOperatorSum	Prunes operators from an OperatorSum based on their effective norm (in-place).
prune(RealOperatorSum input, real tolerance) -> RealOperatorSum	Prunes operators from an OperatorSum based on their effective norm (in-place).
prune(ComplexOperatorSum input, real tolerance) -> ComplexOperatorSum	Prunes operators from an OperatorSum based on their effective norm (in-place).
prune(RealOperatorSum input) -> RealOperatorSum	Prunes operators from an OperatorSum based on their effective norm (in-place).

prune(ComplexOperatorSum input) -> ComplexOperatorSum

Prunes operators from an OperatorSum based on their effective norm (in-place).

Here, the effective norm = |coefficient| × norm(operator), where norm(operator) is the spectral norm by default. Uses a default cutoff threshold of 1e-13 for double and 1e-4 for single precision. To modify the cutoff, use the tolerance parameter version.

Parameters

• input: The input OperatorSum to be modified in-place

Returns

Reference to the modified OperatorSum (allows method chaining)

Example

var sum = X(0) + 1e-15 * Y(0);
prune(sum);                    // sum is modified to contain only 1 * X(0)

// Alternative syntax:
sum.prune();                   // Same result, member function style

// Method chaining example:
var result = prune(sum);       // result refers to the same modified sum

prune(RealOperatorSum input, real tolerance) -> RealOperatorSum

Prunes operators from an OperatorSum based on their effective norm (in-place).

Here, the effective norm = |coefficient| × norm(operator), where norm(operator) is the spectral norm by default. This version allows you to specify a custom cutoff threshold.

Parameters

• input: The input OperatorSum to be modified in-place
• tolerance: The custom threshold below which terms are removed (optional)

Returns

Reference to the modified OperatorSum (allows method chaining)

Example

var sum = X(0) + 1e-4 * Y(0);
prune(sum, 1e-3);                 // sum is modified to contain only 1 * X(0)

// Alternative syntax:
sum.prune(1e-3);                  // Same result, member function style

// Method chaining example:
var result = prune(sum, 1e-3);    // result refers to the same modified sum

prune(ComplexOperatorSum input, real tolerance) -> ComplexOperatorSum

Prunes operators from an OperatorSum based on their effective norm (in-place).

Here, the effective norm = |coefficient| × norm(operator), where norm(operator) is the spectral norm by default. This version allows you to specify a custom cutoff threshold.

Parameters

• input: The input OperatorSum to be modified in-place
• tolerance: The custom threshold below which terms are removed (optional)

Returns

Reference to the modified OperatorSum (allows method chaining)

Example

var sum = X(0) + 1e-4 * Y(0);
prune(sum, 1e-3);                 // sum is modified to contain only 1 * X(0)

// Alternative syntax:
sum.prune(1e-3);                  // Same result, member function style

// Method chaining example:
var result = prune(sum, 1e-3);    // result refers to the same modified sum

prune(RealOperatorSum input) -> RealOperatorSum

Prunes operators from an OperatorSum based on their effective norm (in-place).

Here, the effective norm = |coefficient| × norm(operator), where norm(operator) is the spectral norm by default. Uses a default cutoff threshold of 1e-13 for double and 1e-4 for single precision. To modify the cutoff, use the tolerance parameter version.

Parameters

• input: The input OperatorSum to be modified in-place

Returns

Reference to the modified OperatorSum (allows method chaining)

Example

var sum = X(0) + 1e-15 * Y(0);
prune(sum);                    // sum is modified to contain only 1 * X(0)

// Alternative syntax:
sum.prune();                   // Same result, member function style

// Method chaining example:
var result = prune(sum);       // result refers to the same modified sum