PFA object and related elements

The PFAType definition.

class sarpy.io.complex.sicd_elements.PFA.STDeskewType(Applied: bool = None, STDSPhasePoly: Poly2DType | ndarray | list | tuple = None, **kwargs)

Bases: Serializable

Parameters to describe image domain ST Deskew processing.

Applied: bool

Parameter indicating if slow time (ST) Deskew Phase function has been applied. Required.

Type:

bool

STDSPhasePoly: Poly2DType

Slow time deskew phase function to perform the ST/Kaz shift. Two-dimensional phase (cycles) polynomial function of image range coordinate (variable 1) and azimuth coordinate (variable 2). Required.

Type:

Poly2DType

copy()

Create a deep copy.

classmethod from_dict(input_dict)

For json deserialization, from dict instance.

Parameters:

input_dict (dict) – Appropriate parameters dict instance for deserialization

Return type:

Corresponding class instance

classmethod from_node(node, xml_ns, ns_key=None, kwargs=None)

For XML deserialization.

Parameters:

  • node (ElementTree.Element) – dom element for serialized class instance

  • xml_ns (None|dict) – The xml namespace dictionary.

  • ns_key (None|str) – The xml namespace key. If xml_ns is None, then this is ignored. If None and xml_ns is not None, then the string default will be used. This will be recursively passed down, unless overridden by an entry of the cls._child_xml_ns_key dictionary.

  • kwargs (None|dict) – None or dictionary of previously serialized attributes. For use in inheritance call, when certain attributes require specific deserialization.

Return type:

Corresponding class instance

is_valid(recursive=False, stack=False)

Returns the validity of this object according to the schema. This is done by inspecting that all required fields (i.e. entries of _required) are not None.

Parameters:

  • recursive (bool) – True if we recursively check that child are also valid. This may result in verbose (i.e. noisy) logging.

  • stack (bool) – Print a recursive error message?

Returns:

condition for validity of this element

Return type:

bool

log_validity_error(msg)

Log a validity check error message.

Parameters:

msg (str) –

log_validity_info(msg)

Log a validation info message.

Parameters:

msg (str) –

log_validity_warning(msg)

Log a validity check warning message.

Parameters:

msg (str) –

set_numeric_format(attribute, format_string)

Sets the numeric format string for the given attribute.

Parameters:

  • attribute (str) – attribute for which the format applies - must be in _fields.

  • format_string (str) – format string to be applied

Return type:

None

to_dict(check_validity=False, strict=False, exclude=())

For json serialization.

Parameters:

  • check_validity (bool) – Check whether the element is valid before serializing, by calling is_valid().

  • strict (bool) – Only used if check_validity = True. In that case, if True then raise an Exception (of appropriate type) if the structure is not valid, if False then log a hopefully helpful message.

  • exclude (tuple) – Attribute names to exclude from this generic serialization. This allows for child classes to provide specific serialization for special properties, after using this super method.

Returns:

dict representation of class instance appropriate for direct json serialization.

Return type:

OrderedDict

to_node(doc, tag, ns_key=None, parent=None, check_validity=False, strict=False, exclude=())

For XML serialization, to a dom element.

Parameters:

  • doc (ElementTree.ElementTree) – The xml Document

  • tag (None|str) – The tag name. Defaults to the value of self._tag and then the class name if unspecified.

  • ns_key (None|str) – The namespace prefix. This will be recursively passed down, unless overridden by an entry in the _child_xml_ns_key dictionary.

  • parent (None|ElementTree.Element) – The parent element. Defaults to the document root element if unspecified.

  • check_validity (bool) – Check whether the element is valid before serializing, by calling is_valid().

  • strict (bool) – Only used if check_validity = True. In that case, if True then raise an Exception (of appropriate type) if the structure is not valid, if False then log a hopefully helpful message.

  • exclude (tuple) – Attribute names to exclude from this generic serialization. This allows for child classes to provide specific serialization for special properties, after using this super method.

Returns:

The constructed dom element, already assigned to the parent element.

Return type:

ElementTree.Element

to_xml_bytes(urn=None, tag=None, check_validity=False, strict=False)

Gets a bytes array, which corresponds to the xml string in utf-8 encoding, identified as using the namespace given by urn (if given).

Parameters:

  • urn (None|str|dict) – The xml namespace string or dictionary describing the xml namespace.

  • tag (None|str) – The root node tag to use. If not given, then the class name will be used.

  • check_validity (bool) – Check whether the element is valid before serializing, by calling is_valid().

  • strict (bool) – Only used if check_validity = True. In that case, if True then raise an Exception (of appropriate type) if the structure is not valid, if False then log a hopefully helpful message.

Returns:

bytes array from ElementTree.tostring() call.

Return type:

bytes

to_xml_string(urn=None, tag=None, check_validity=False, strict=False)

Gets a xml string with utf-8 encoding, identified as using the namespace given by urn (if given).

Parameters:

  • urn (None|str|dict) – The xml namespace or dictionary describing the xml namespace.

  • tag (None|str) – The root node tag to use. If not given, then the class name will be used.

  • check_validity (bool) – Check whether the element is valid before serializing, by calling is_valid().

  • strict (bool) – Only used if check_validity = True. In that case, if True then raise an Exception (of appropriate type) if the structure is not valid, if False then log a hopefully helpful message.

Returns:

xml string from ElementTree.tostring() call.

Return type:

str

class sarpy.io.complex.sicd_elements.PFA.PFAType(FPN: XYZType | ndarray | list | tuple = None, IPN: XYZType | ndarray | list | tuple = None, PolarAngRefTime: float = None, PolarAngPoly: Poly1DType | ndarray | list | tuple = None, SpatialFreqSFPoly: Poly1DType | ndarray | list | tuple = None, Krg1: float = None, Krg2: float = None, Kaz1: float = None, Kaz2: float = None, STDeskew: STDeskewType | None = None, **kwargs)

Bases: Serializable

Parameters for the Polar Formation Algorithm.

FPN: XYZType

Focus Plane unit normal in ECF coordinates. Unit vector FPN points away from the center of the Earth. Required.

Type:

XYZType

IPN: XYZType

Image Formation Plane unit normal in ECF coordinates. Unit vector IPN points away from the center of the Earth. Required.

Type:

XYZType

PolarAngRefTime: float

Reference time is typically set equal to the SCP COA time but may be different.* Required.

Type:

float

Type:

Polar image formation reference time (in seconds). Polar Angle = 0 at the reference time. Measured relative to collection start. *Note

copy()

Create a deep copy.

classmethod from_dict(input_dict)

For json deserialization, from dict instance.

Parameters:

input_dict (dict) – Appropriate parameters dict instance for deserialization

Return type:

Corresponding class instance

classmethod from_node(node, xml_ns, ns_key=None, kwargs=None)

For XML deserialization.

Parameters:

  • node (ElementTree.Element) – dom element for serialized class instance

  • xml_ns (None|dict) – The xml namespace dictionary.

  • ns_key (None|str) – The xml namespace key. If xml_ns is None, then this is ignored. If None and xml_ns is not None, then the string default will be used. This will be recursively passed down, unless overridden by an entry of the cls._child_xml_ns_key dictionary.

  • kwargs (None|dict) – None or dictionary of previously serialized attributes. For use in inheritance call, when certain attributes require specific deserialization.

Return type:

Corresponding class instance

is_valid(recursive=False, stack=False)

Returns the validity of this object according to the schema. This is done by inspecting that all required fields (i.e. entries of _required) are not None.

Parameters:

  • recursive (bool) – True if we recursively check that child are also valid. This may result in verbose (i.e. noisy) logging.

  • stack (bool) – Print a recursive error message?

Returns:

condition for validity of this element

Return type:

bool

log_validity_error(msg)

Log a validity check error message.

Parameters:

msg (str) –

log_validity_info(msg)

Log a validation info message.

Parameters:

msg (str) –

log_validity_warning(msg)

Log a validity check warning message.

Parameters:

msg (str) –

set_numeric_format(attribute, format_string)

Sets the numeric format string for the given attribute.

Parameters:

  • attribute (str) – attribute for which the format applies - must be in _fields.

  • format_string (str) – format string to be applied

Return type:

None

to_dict(check_validity=False, strict=False, exclude=())

For json serialization.

Parameters:

  • check_validity (bool) – Check whether the element is valid before serializing, by calling is_valid().

  • strict (bool) – Only used if check_validity = True. In that case, if True then raise an Exception (of appropriate type) if the structure is not valid, if False then log a hopefully helpful message.

  • exclude (tuple) – Attribute names to exclude from this generic serialization. This allows for child classes to provide specific serialization for special properties, after using this super method.

Returns:

dict representation of class instance appropriate for direct json serialization.

Return type:

OrderedDict

to_node(doc, tag, ns_key=None, parent=None, check_validity=False, strict=False, exclude=())

For XML serialization, to a dom element.

Parameters:

  • doc (ElementTree.ElementTree) – The xml Document

  • tag (None|str) – The tag name. Defaults to the value of self._tag and then the class name if unspecified.

  • ns_key (None|str) – The namespace prefix. This will be recursively passed down, unless overridden by an entry in the _child_xml_ns_key dictionary.

  • parent (None|ElementTree.Element) – The parent element. Defaults to the document root element if unspecified.

  • check_validity (bool) – Check whether the element is valid before serializing, by calling is_valid().

  • strict (bool) – Only used if check_validity = True. In that case, if True then raise an Exception (of appropriate type) if the structure is not valid, if False then log a hopefully helpful message.

  • exclude (tuple) – Attribute names to exclude from this generic serialization. This allows for child classes to provide specific serialization for special properties, after using this super method.

Returns:

The constructed dom element, already assigned to the parent element.

Return type:

ElementTree.Element

to_xml_bytes(urn=None, tag=None, check_validity=False, strict=False)

Gets a bytes array, which corresponds to the xml string in utf-8 encoding, identified as using the namespace given by urn (if given).

Parameters:

  • urn (None|str|dict) – The xml namespace string or dictionary describing the xml namespace.

  • tag (None|str) – The root node tag to use. If not given, then the class name will be used.

  • check_validity (bool) – Check whether the element is valid before serializing, by calling is_valid().

  • strict (bool) – Only used if check_validity = True. In that case, if True then raise an Exception (of appropriate type) if the structure is not valid, if False then log a hopefully helpful message.

Returns:

bytes array from ElementTree.tostring() call.

Return type:

bytes

to_xml_string(urn=None, tag=None, check_validity=False, strict=False)

Gets a xml string with utf-8 encoding, identified as using the namespace given by urn (if given).

Parameters:

  • urn (None|str|dict) – The xml namespace or dictionary describing the xml namespace.

  • tag (None|str) – The root node tag to use. If not given, then the class name will be used.

  • check_validity (bool) – Check whether the element is valid before serializing, by calling is_valid().

  • strict (bool) – Only used if check_validity = True. In that case, if True then raise an Exception (of appropriate type) if the structure is not valid, if False then log a hopefully helpful message.

Returns:

xml string from ElementTree.tostring() call.

Return type:

str

PolarAngPoly: Poly1DType

Polynomial function that yields Polar Angle (in radians) as function of time relative to Collection Start. Required.

Type:

Poly1DType

SpatialFreqSFPoly: Poly1DType

Polynomial that yields the Spatial Frequency Scale Factor (KSF) as a function of Polar Angle. That is, \(Polar Angle[radians] \to KSF[dimensionless]\). Used to scale RF frequency (fx, Hz) to aperture spatial frequency (Kap, cycles/m). Where,:math:Kap = fxcdot (2/c)cdot KSF, and Kap is the effective spatial frequency in the polar aperture. Required.

Type:

Poly1DType

Krg1: float

Minimum range spatial frequency (Krg) output from the polar to rectangular resampling. Required.

Type:

float

Krg2: float

Maximum range spatial frequency (Krg) output from the polar to rectangular resampling. Required.

Type:

float

Kaz1: float

Minimum azimuth spatial frequency (Kaz) output from the polar to rectangular resampling. Required.

Type:

float

Kaz2: float

Maximum azimuth spatial frequency (Kaz) output from the polar to rectangular resampling. Required.

Type:

float

STDeskew: STDeskewType

Parameters to describe image domain slow time (ST) Deskew processing. Optional.

Type:

STDeskewType

pfa_polar_coords(Position, SCP: ndarray, times: float | int | ndarray) → Tuple[None | float | ndarray, None | float | ndarray]

Calculate the PFA parameters necessary for mapping phase history to polar coordinates.

Parameters:
Returns:

  • k_a (None|float|numpy.ndarray) – The polar angle

  • k_sf (None|float|numpy.ndarray) – The spatial frequency scale factor. The shape of the return arrays will match the shape of the times array (or scalar).