Polynomial

Description

A filter response given in terms of a polynomial expansion of powers of the sensor output signal. The coefficients are Maclaurin coefficients for the given frequency and approximation ranges.

Python class:

Polynomial

YAML / JSON label:

polynomial

Corresponding StationXML structure

Polynomial

Object Hierarchy

Superclass

Filter_Template

Subclasses

None

Relationships

Is nested in Stage

Attributes

Name	Type	Required	Default	Equivalent StationXML	Remarks
type	string (must be “Polynomial”)	Y	None	None
coefficients	Array of Maclaurin Coefficients	Y	None	Coefficients
frequency_lower_bound	number	Y	None	FrequencyLowerBound
frequency_upper_bound	number	Y	None	FrequencyUpperBound
approximation_lower_bound	number	Y	None	ApproximationLowerBound
approximation_upper_bound	number	Y	None	ApproximationUpperBound
maximum_error	number	Y	None	MaximumError
approximation_type	string (must be “MACLAURIN”)	Y	None	ApproximationType
resource_id:	string (“GENERATOR:Meaningful ID”)	N	None	ResourceId

JSON schema

https://www.gitlab.com/resif/smm/obsinfo/-/tree/master/obsinfo/data/schemas/filter.schema.json

Example

_templates/TEMPLATE.polynomial.filter.yaml

---
format_version: "1.0"
revision:
   authors:
        - {$ref: "persons/EXAMPLE.person.yaml"} # Reference to a file,
                                                 # or fields of a person element
   date: "2024-09-30" # yyyy-mm-dd
# WARNING!  OBSPY 1.4.0 does not handle Polynomial filters
filter:
   type: "Polynomial"
   coefficients :
       - value: 10     # Simple expression
       -        # Full expression
            value: 20
            # BEGIN OPTIONAL coefficient elements
            plus_error: 1.
            minus_error: 1.
            measurement_method: "johnson a2 microcalipers"
            number: 2      # 0 or positive integer
            # END OPTIONAL coefficient elements
   frequency_lower_bound: 
        value: 0.001
        # BEGIN OPTIONAL frequency_bound elements
        unit: "HERTZ"   # ("HERTZ"), no other value is allowed!
        plus_error: 0.001
        minus_error: 0.001
        measurement_method: "oscilloscope"
        # END OPTIONAL frequency_bound elements
   frequency_upper_bound:
        value: 0.1
        # BEGIN OPTIONAL frequency_bound elements
        unit: "HERTZ"   # ("HERTZ"), no other value is allowed!
        plus_error: 0.1
        minus_error: 0.1
        measurement_method: "oscilloscope"
        # END OPTIONAL frequency_bound elements
   approximation_lower_bound: 3.    # Lower bound of the approximation range
   approximation_upper_bound: 5.    # Upper bound of the approximation range
   maximum_error: 0.2               # Maximum error of the approximatiion
   # BEGIN OPTIONAL filter elements
   approximation_type: "MACLAURIN"  # ("MACLAURIN"), no other value allowed!
   # END OPTIONAL filter elements
# BEGIN OPTIONAL top-level elements
notes: 
   - ""
# END OPTIONAL top-level elements