EvaluatorInstructions

Symbolica documentation for getting started, symbolic expressions, numerical evaluation, pattern matching, and APIs in Python and Rust.

`EvaluatorInstructions`

class EvaluatorInstructions

A structured instruction stream for evaluating an expression.

Attributes

Name	Description
`constant_functions`	Registered constants and fixed-argument functions (such as `pi`) held in `('const', index)` slots
`constants`	Exact constants referenced by `('const', index)` slots.
`input_count`	The number of input parameter values expected by this instruction stream.
`instructions`	Return a structured instruction representation for efficiently evaluating the expression
`output_count`	The number of output values produced by this instruction stream.
`sub_evaluators`	Non-inlined function bodies referenced by `fun` instructions in this stream.
`temporary_count`	The number of temporary storage slots required by `instructions`.

`constant_functions`

EvaluatorInstructions.constant_functions: list[EvaluatorConstantFunction]

Registered constants and fixed-argument functions (such as pi) held in ('const', index) slots. Each entry exposes index, function, tags, and arguments. The exact constants hold placeholders at these indices: evaluate function with its tags at the exact arguments in the target precision before using such a slot.

`constants`

EvaluatorInstructions.constants: list[Expression]

Exact constants referenced by ('const', index) slots.

`input_count`

EvaluatorInstructions.input_count: int

The number of input parameter values expected by this instruction stream.

`instructions`

EvaluatorInstructions.instructions: list[tuple]

Return a structured instruction representation for efficiently evaluating the expression. This can be used to generate code for the expression evaluation in any programming language. Function names and tags remain Expression objects.

There are four lists that are used in the evaluation instructions:

param: the list of input parameters.
temp: the list of temporary slots. Its size is available as temporary_count.
const: the list of constants.
out: the list of outputs.

The instructions are of the form:

('add', ('out', 0), [('const', 1), ('param', 0)], 0) which means out[0] = const[1] + param[0] where the first 0 arguments are real.
('mul', ('out', 0), [('temp', 0), ('param', 0)], 1) which means out[0] = temp[0] * param[0], where the first 1 arguments are real.
('pow', ('out', 0), ('param', 0), -1, true) which means out[0] = param[0]^-1 and the output is real (true).
('powf', ('out', 0), ('param', 0), ('param', 1), false) which means out[0] = param[0]^param[1].
('fun', ('temp', 1), f, [Expression.num(0)], [('param', 0)], true) which means temp[1] = f(0, param[0]) and the output is real (true).
('if_else', ('temp', 0), 5) which means if temp[0] == 0 goto label 5 (false branch).
('goto', 10) which means goto label 10.
('label', 3) which means label 3.
('join', ('out', 0), ('temp', 0), 3, 7) which means out[0] = (temp[0] != 0) ? label 3 : label 7.

`output_count`

EvaluatorInstructions.output_count: int

The number of output values produced by this instruction stream.

`sub_evaluators`

EvaluatorInstructions.sub_evaluators: list[EvaluatorFunction]

Non-inlined function bodies referenced by fun instructions in this stream.

`temporary_count`

EvaluatorInstructions.temporary_count: int

The number of temporary storage slots required by instructions.

Methods

Name	Description
`__repr__`

`repr`

EvaluatorInstructions.__repr__() -> str