empyrean.SphericalCoordinates¶

class SphericalCoordinates(table, **kwargs)[source]

Bases: Table

Spherical coordinates (topocentric / observer-centric).

Methods

`__init__`(table, **kwargs)
`apply_mask`(mask)	Return a new table with rows filtered to match a boolean mask.
`as_column`([nullable, metadata])	Embed the Table as a column in another Table.
`attributes`()	Return a dictionary of the table's attributes.
`chunk_counts`()	Returns the number of discrete memory chunks that make up each of the Table's underlying arrays.
`column`(column_name)	Returns the column with the given name as a raw pyarrow ChunkedArray.
`drop_duplicates`([subset, keep])	Drop duplicate rows from a ~quivr.Table.
`empty`(**kwargs)	Create an empty instance of the table.
`flattened_table`()	Completely flatten the Table's underlying Arrow table, taking into account any nested structure, and return the data table itself.
`fragmented`()	Returns true if the Table has any fragmented arrays.
`from_csv`(input_file[, validate])	Read a table from a CSV file.
`from_dataframe`(df[, validate])	Load a DataFrame into the Table.
`from_feather`(path[, validate])	Read a table from a Feather file.
`from_flat_dataframe`(df[, validate])	Load a flattened DataFrame into the Table.
`from_kwargs`([validate, permit_nulls])	Create a Table instance from keyword arguments.
`from_parquet`(path[, memory_map, ...])	Read a table from a Parquet file.
`from_pyarrow`(table[, validate, permit_nulls])	Create a new table from a pyarrow Table.
`invalid_mask`()	Return a boolean mask indicating which rows are invalid.
`is_valid`()	Validate the table against the schema.
`null_mask`()	Return a boolean mask indicating which rows of the entire table are null.
`nulls`(size, **kwargs)	Create a table with nulls.
`select`(column_name, value)	Select from the table by exact match, returning a new Table which only contains rows for which the value in column_name equals value.
`separate_invalid`()	Separates rows that have invalid data from those that have valid data.
`set_column`(name, data)	Return a copy of the table with a particular column replaced with new data.
`sort_by`(by)	Sorts the Table by the given column name (or multiple columns).
`take`(row_indices)	Return a new Table with only the rows at the given indices.
`to_csv`(path[, attribute_columns])	Write the table to a CSV file.
`to_dataframe`([flatten, attr_handling])	Returns self as a pandas DataFrame.
`to_feather`(path, **kwargs)	Write the table to a Feather file.
`to_parquet`(path, **kwargs)	Write the table to a Parquet file.
`to_structarray`()	Returns self as a StructArray.
`unique_indices`([subset, keep])	Get the indices of the first or last occurrence of each unique row in the table.
`validate`()	Validate the table against the schema, raising an exception if invalid.
`where`(expr)	Return a new table with rows filtered to match an expression.
`with_table`(table)

Attributes

`covariance`	A column which represents an embedded quivr table.
`epoch`	A column for storing 64-bit floating point numbers.
`frame`	StringAttribute represents a string which is stored as UTF-8 bytes in Table metadata.
`lat`	A column for storing 64-bit floating point numbers.
`lon`	A column for storing 64-bit floating point numbers.
`origin`	A column for storing large strings (over 2³¹ bytes long).
`rho`	A column for storing 64-bit floating point numbers.
`schema`
`unit_vector`	`(N, 3)` topocentric line-of-sight unit vectors in the table's frame.
`vlat`	A column for storing 64-bit floating point numbers.
`vlon`	A column for storing 64-bit floating point numbers.
`vrho`	A column for storing 64-bit floating point numbers.
`table`

Parameters:

table (Table)
kwargs (AttributeValueType)

epoch: A column for storing 64-bit floating point numbers.

rho: A column for storing 64-bit floating point numbers.

lon: A column for storing 64-bit floating point numbers.

lat: A column for storing 64-bit floating point numbers.

vrho: A column for storing 64-bit floating point numbers.

vlon: A column for storing 64-bit floating point numbers.

vlat: A column for storing 64-bit floating point numbers.

covariance

A column which represents an embedded quivr table.

Parameters:

table_type – The type of the table to embed.
nullable – Whether the column can contain null values.
metadata – A dictionary of metadata to attach to the column.

frame

StringAttribute represents a string which is stored as UTF-8 bytes in Table metadata.

Parameters:: default – The default value for this attribute. If no default is provided, then the attribute must be set whenever constructing a table that uses it.

origin: A column for storing large strings (over 2³¹ bytes long). Large string data is stored in variable-length chunks.

property unit_vector: ndarray[Any, dtype[float64]]: (N, 3) topocentric line-of-sight unit vectors in the table’s frame. Useful for ephemeris geometry / angular separations without going through Cartesian.

schema: ClassVar[Schema] = epoch: double not null rho: double not null lon: double not null lat: double not null vrho: double not null vlon: double not null vlat: double not null covariance: struct<cov_rho_rho: double, cov_rho_lon: double, cov_lon_lon: double, cov_rho_lat: double, cov_lon_l (... 368 chars omitted) child 0, cov_rho_rho: double child 1, cov_rho_lon: double child 2, cov_lon_lon: double child 3, cov_rho_lat: double child 4, cov_lon_lat: double child 5, cov_lat_lat: double child 6, cov_rho_vrho: double child 7, cov_lon_vrho: double child 8, cov_lat_vrho: double child 9, cov_vrho_vrho: double child 10, cov_rho_vlon: double child 11, cov_lon_vlon: double child 12, cov_lat_vlon: double child 13, cov_vrho_vlon: double child 14, cov_vlon_vlon: double child 15, cov_rho_vlat: double child 16, cov_lon_vlat: double child 17, cov_lat_vlat: double child 18, cov_vrho_vlat: double child 19, cov_vlon_vlat: double child 20, cov_vlat_vlat: double origin: large_string not null