empyrean.NonGravParams

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

Bases: Table

Non-gravitational acceleration parameters.

Model types:

“marsden_water” – Marsden-Sekanina with standard H2O sublimation g(r) “inverse_square” – Marsden-Sekanina with g(r) = 1/r^2 (Yarkovsky) “marsden” – Marsden-Sekanina with custom g(r) exponents “srp” – Solar radiation pressure from AMRAT (a1 = AMRAT in m^2/kg)

For “marsden”, the g(r) function is:

g(r) = alpha * (r/r0)^{-m} * (1 + (r/r0)^n)^{-k}

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

a1

A column for storing 64-bit floating point numbers.

a2

A column for storing 64-bit floating point numbers.

a3

A column for storing 64-bit floating point numbers.

alpha

A column for storing 64-bit floating point numbers.

cr

A column for storing 64-bit floating point numbers.

dt

A column for storing 64-bit floating point numbers.

k

A column for storing 64-bit floating point numbers.

m

A column for storing 64-bit floating point numbers.

model

A column for storing large strings (over 231 bytes long).

n

A column for storing 64-bit floating point numbers.

r0

A column for storing 64-bit floating point numbers.

schema

table

Parameters:
  • table (Table)

  • kwargs (AttributeValueType)

a1

A column for storing 64-bit floating point numbers.

a2

A column for storing 64-bit floating point numbers.

a3

A column for storing 64-bit floating point numbers.

model

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

alpha

A column for storing 64-bit floating point numbers.

r0

A column for storing 64-bit floating point numbers.

m

A column for storing 64-bit floating point numbers.

n

A column for storing 64-bit floating point numbers.

k

A column for storing 64-bit floating point numbers.

cr

A column for storing 64-bit floating point numbers.

dt

A column for storing 64-bit floating point numbers.

schema: ClassVar[Schema] = a1: double not null a2: double not null a3: double not null model: large_string not null alpha: double r0: double m: double n: double k: double cr: double dt: double