Sidereon.CCSDS.OEM (Sidereon v3.0.0)

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Parse and encode CCSDS Orbit Ephemeris Messages (OEM).

Supports both the KVN (Keyword=Value Notation) and XML formats per CCSDS 502.0-B. An OEM carries one or more segments, each a metadata block plus a time-ordered list of Cartesian state samples (optionally with acceleration) and optional covariance blocks. The header, metadata and every comment are kept: header and metadata comments in their blocks, and the comments among the state lines and covariance matrices at their positions, which the writers restore.

parse/1 auto-detects the format from the first non-whitespace character: a leading < is treated as XML, anything else as KVN. Date/time fields are preserved as raw strings exactly as written; the message round-trips through the canonical struct without calendar rewriting.

Examples

{:ok, oem} = Sidereon.CCSDS.OEM.parse(kvn_string)
[segment | _] = oem.segments
segment.metadata.object_name
[state | _] = segment.states
state.position_km            # {x, y, z} in km

# KVN output (default)
{:ok, kvn} = Sidereon.CCSDS.OEM.encode(oem)

# XML output
{:ok, xml} = Sidereon.CCSDS.OEM.encode(oem, format: :xml)

# Round-trip through XML
{:ok, oem2} = Sidereon.CCSDS.OEM.parse(xml)

Summary

Types

error()

Failure reason from the OEM readers and writers, with every field the core refusal carries (Sidereon.CCSDS.Error.oem/0): a missing or invalid field, a malformed value, a keyword repeated with a different value, a unit that contradicts the standard's table, a document holding several messages, a keyword the standard does not define at its position, a KVN line that is not blank, a comment or an assignment, text a writer cannot write so that its reader returns it unchanged, or (writers only) fields that do not form a message, such as a covariance without exactly 21 lower-triangle values.

t()

A CCSDS OEM. comments are the header comments. skipped_states lists the KVN ephemeris data lines the reader skipped; the writers do not write them.

vec3()

A Cartesian triple {x, y, z}.

Functions

encode(oem, opts \\ [])

Encode an OEM.

encode_kvn(oem)

Encode an OEM to KVN text explicitly. Returns {:ok, text} or {:error, reason}.

encode_xml(oem)

Encode an OEM to XML text explicitly. Returns {:ok, text} or {:error, reason}.

parse(string)

Parse an OEM in either KVN or XML format.

parse_kvn(text)

Parse an OEM in KVN format explicitly. Skips format auto-detection.

parse_xml(text)

Parse an OEM in XML format explicitly. Skips format auto-detection.

Types

error()

@type error() :: Sidereon.CCSDS.Error.oem()

Failure reason from the OEM readers and writers, with every field the core refusal carries (Sidereon.CCSDS.Error.oem/0): a missing or invalid field, a malformed value, a keyword repeated with a different value, a unit that contradicts the standard's table, a document holding several messages, a keyword the standard does not define at its position, a KVN line that is not blank, a comment or an assignment, text a writer cannot write so that its reader returns it unchanged, or (writers only) fields that do not form a message, such as a covariance without exactly 21 lower-triangle values.

t()

@type t() :: %Sidereon.CCSDS.OEM{
  ccsds_oem_vers: String.t(),
  classification: String.t() | nil,
  comments: [String.t()],
  creation_date: String.t() | nil,
  message_id: String.t() | nil,
  originator: String.t() | nil,
  segments: [Sidereon.CCSDS.OEM.Segment.t()],
  skipped_states: [Sidereon.CCSDS.OEM.SkippedState.t()]
}

A CCSDS OEM. comments are the header comments. skipped_states lists the KVN ephemeris data lines the reader skipped; the writers do not write them.

vec3()

@type vec3() :: {float(), float(), float()}

A Cartesian triple {x, y, z}.

Functions

encode(oem, opts \\ [])

@spec encode(
  t(),
  keyword()
) :: {:ok, String.t()} | {:error, error()}

Encode an OEM.

Returns {:ok, text}, or {:error, reason} for a message the writer cannot write so that its reader returns it unchanged (see error/0).

Options

  • :format - :kvn (default) or :xml

encode_kvn(oem)

@spec encode_kvn(t()) :: {:ok, String.t()} | {:error, error()}

Encode an OEM to KVN text explicitly. Returns {:ok, text} or {:error, reason}.

encode_xml(oem)

@spec encode_xml(t()) :: {:ok, String.t()} | {:error, error()}

Encode an OEM to XML text explicitly. Returns {:ok, text} or {:error, reason}.

parse(string)

@spec parse(String.t()) :: {:ok, t()} | {:error, error()}

Parse an OEM in either KVN or XML format.

Format is auto-detected from the first non-whitespace character: < routes to the XML parser, anything else to the KVN parser.

Returns {:ok, %Sidereon.CCSDS.OEM{}} or {:error, reason}.

parse_kvn(text)

@spec parse_kvn(String.t()) :: {:ok, t()} | {:error, error()}

Parse an OEM in KVN format explicitly. Skips format auto-detection.

parse_xml(text)

@spec parse_xml(String.t()) :: {:ok, t()} | {:error, error()}

Parse an OEM in XML format explicitly. Skips format auto-detection.