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    • astropy
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    • specutils
  • Get Help
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Astropy v8.1.0.dev666+g006f4960a

  • Getting Started
    • Installation
    • Importing astropy and Sub-packages
    • Tutorials
  • User Guide
    • Constants (astropy.constants)
      • Constant
      • EMConstant
    • Units and Quantities (astropy.units)
      • Quantity
      • Unit-Aware Type Annotations
      • Standard Units
      • Combining and Defining Units
      • Decomposing and Composing Units
      • Magnitudes and Other Logarithmic Units
      • Structured Units
      • String Representations of Units and Quantities
      • Equivalencies
      • Physical Types
      • Using Prior Versions of Constants
      • Low-Level Unit Conversion
      • Reference/API
        • add_enabled_aliases
        • add_enabled_equivalencies
        • add_enabled_units
        • allclose
        • beam_angular_area
        • brightness_temperature
        • def_physical_type
        • def_unit
        • dimensionless_angles
        • doppler_optical
        • doppler_radio
        • doppler_redshift
        • doppler_relativistic
        • get_current_unit_registry
        • get_physical_type
        • isclose
        • logarithmic
        • magnetic_flux_field
        • mass_energy
        • molar_mass_amu
        • parallax
        • pixel_scale
        • plate_scale
        • preserve_dtype_by_default
        • quantity_input
        • set_enabled_aliases
        • set_enabled_equivalencies
        • set_enabled_units
        • spectral
        • spectral_density
        • temperature
        • temperature_energy
        • thermodynamic_temperature
        • zero_point_flux
        • CompositeUnit
        • Decibel
        • DecibelUnit
        • Dex
        • DexUnit
        • Equivalency
        • FunctionQuantity
        • FunctionUnitBase
        • IrreducibleUnit
        • LogQuantity
        • LogUnit
        • MagUnit
        • Magnitude
        • NamedUnit
        • PhysicalType
        • PrefixUnit
        • Quantity
        • QuantityInfo
        • QuantityInfoBase
        • SpecificTypeQuantity
        • StructuredUnit
        • Unit
        • UnitBase
        • UnitConversionError
        • UnitParserWarning
        • UnitPrefix
        • UnitScaleError
        • UnitTypeError
        • UnitsError
        • UnitsWarning
        • UnrecognizedUnit
        • enable
        • enable
        • def_physical_type
        • get_physical_type
        • PhysicalType
        • get_format
        • CDS
        • FITS
        • OGIP
        • Base
        • Console
        • Generic
        • Latex
        • LatexInline
        • Unicode
        • VOUnit
    • N-Dimensional Datasets (astropy.nddata)
      • CCDData Class
      • Image Utilities
      • Utility Functions for Handling Bit Masks and Mask Arrays
      • Decorating Functions to Accept NDData Objects
      • NDData
      • Covariance
      • Mixins for Added Functionality
        • Slicing and Indexing NDData
        • NDData Arithmetic
        • I/O Mixin
      • Subclassing
      • Reference/API
        • add_array
        • bitfield_to_boolean_mask
        • block_reduce
        • block_replicate
        • extend_bit_flag_map
        • extract_array
        • fits_ccddata_reader
        • fits_ccddata_writer
        • interpret_bit_flags
        • overlap_slices
        • reshape_as_blocks
        • subpixel_indices
        • support_nddata
        • BitFlagNameMap
        • CCDData
        • Conf
        • Covariance
        • Cutout2D
        • FlagCollection
        • IncompatibleUncertaintiesException
        • InvalidBitFlag
        • InverseVariance
        • MissingDataAssociationException
        • NDArithmeticMixin
        • NDData
        • NDDataArray
        • NDDataBase
        • NDDataRef
        • NDIOMixin
        • NDSlicingMixin
        • NDUncertainty
        • NoOverlapError
        • PartialOverlapError
        • StdDevUncertainty
        • UnknownUncertainty
        • VarianceUncertainty
        • bitfield_to_boolean_mask
        • extend_bit_flag_map
        • interpret_bit_flags
        • BitFlagNameMap
        • InvalidBitFlag
        • add_array
        • extract_array
        • overlap_slices
        • subpixel_indices
        • Cutout2D
        • NoOverlapError
        • PartialOverlapError
    • Data Tables (astropy.table)
      • Constructing a Table
      • Accessing a Table
      • Modifying a Table
      • Table Operations
      • Table Indexing
      • Masking and Missing Values
      • Mixin Columns
      • Interfacing with DataFrames
      • Interfacing with the Pandas Package
      • Astropy Table and DataFrames
      • Table Implementation Details
      • Reference/API
        • dstack
        • hstack
        • join
        • join_distance
        • join_skycoord
        • represent_mixins_as_columns
        • represent_nd_columns_as_1d_columns
        • setdiff
        • unique
        • vstack
        • BST
        • Column
        • ColumnGroups
        • ColumnInfo
        • Conf
        • JSViewer
        • MaskedColumn
        • NdarrayMixin
        • PprintIncludeExclude
        • QTable
        • Row
        • SCEngine
        • SerializedColumn
        • SortedArray
        • StringTruncateWarning
        • Table
        • TableAttribute
        • TableColumns
        • TableFormatter
        • TableGroups
        • TableMergeError
        • TableReplaceWarning
        • classic
        • ipydatagrid
    • Time and Dates (astropy.time)
      • Reference/API
        • update_leap_seconds
        • AstropyDatetimeLeapSecondWarning
        • Conf
        • OperandTypeError
        • ScaleValueError
        • Time
        • TimeBase
        • TimeBesselianEpoch
        • TimeBesselianEpochString
        • TimeCxcSec
        • TimeDatetime
        • TimeDatetime64
        • TimeDecimalYear
        • TimeDelta
        • TimeDeltaDatetime
        • TimeDeltaFormat
        • TimeDeltaJD
        • TimeDeltaMissingUnitWarning
        • TimeDeltaNumeric
        • TimeDeltaQuantityString
        • TimeDeltaSec
        • TimeEpochDate
        • TimeEpochDateString
        • TimeFITS
        • TimeFormat
        • TimeFromEpoch
        • TimeGPS
        • TimeGalexSec
        • TimeISO
        • TimeISOT
        • TimeInfo
        • TimeInfoBase
        • TimeJD
        • TimeJulianEpoch
        • TimeJulianEpochString
        • TimeMJD
        • TimeNumeric
        • TimePlotDate
        • TimeString
        • TimeUnique
        • TimeUnix
        • TimeUnixTai
        • TimeYMDHMS
        • TimeYearDayTime
        • TimezoneInfo
    • Time Series (astropy.timeseries)
      • Creating Time Series
      • Reading and Writing Time Series
      • Accessing Data in Time Series
      • Converting between Different Time Representations
      • Manipulation and Analysis of Time Series
      • Masking Values in Time Series
      • Interfacing with the Pandas Package
      • Lomb-Scargle Periodograms
      • Lomb-Scargle Periodograms for Multiband Data
      • Box Least Squares (BLS) Periodogram
      • Reference/API
        • aggregate_downsample
        • autocheck_required_columns
        • BasePeriodogram
        • BaseTimeSeries
        • BinnedTimeSeries
        • BoxLeastSquares
        • BoxLeastSquaresResults
        • LombScargle
        • LombScargleMultiband
        • TimeSeries
        • kepler_fits_reader
    • Astronomical Coordinate Systems (astropy.coordinates)
      • Working with Angles
      • Using the SkyCoord High-Level Class
      • Transforming between Systems
      • Solar System Ephemerides
      • Working with Earth Satellites Using Astropy Coordinates
      • Formatting Coordinate Strings
      • Separations, Offsets, Catalog Matching, and Related Functionality
      • Using and Designing Coordinate Representations
      • Using and Designing Coordinate Frames
      • Working with Velocities in Astropy Coordinates
      • Accounting for Space Motion
      • Using the SpectralCoord Class
      • Using the StokesCoord Class
      • Description of the Galactocentric Coordinate Frame
      • Usage Tips/Suggestions for Methods That Access Remote Resources
      • Common mistakes
      • Important Definitions
      • Fast In-Place Modification of Coordinates
      • Example Gallery
        • Transforming positions and velocities to and from a Galactocentric frame
        • Create a new coordinate frame class for Mars
        • Determining and plotting the altitude/azimuth of a celestial object
        • Create a new coordinate class (for the Sagittarius stream)
        • Convert a radial velocity to the Galactic Standard of Rest (GSR)
      • Reference/API
        • angular_separation
        • cartesian_to_spherical
        • concatenate
        • concatenate_representations
        • custom_stokes_symbol_mapping
        • get_body
        • get_body_barycentric
        • get_body_barycentric_posvel
        • get_constellation
        • get_icrs_coordinates
        • get_sun
        • golden_spiral_grid
        • is_rotation_or_reflection
        • make_transform_graph_docs
        • match_coordinates_3d
        • match_coordinates_sky
        • offset_by
        • position_angle
        • rotation_matrix
        • search_around_3d
        • search_around_sky
        • spherical_to_cartesian
        • uniform_spherical_random_surface
        • uniform_spherical_random_volume
        • AffineTransform
        • AltAz
        • Angle
        • Attribute
        • BarycentricMeanEcliptic
        • BarycentricTrueEcliptic
        • BaseAffineTransform
        • BaseBodycentricRepresentation
        • BaseCoordinateFrame
        • BaseDifferential
        • BaseEclipticFrame
        • BaseGeodeticRepresentation
        • BaseRADecFrame
        • BaseRepresentation
        • BaseRepresentationOrDifferential
        • BaseSphericalCosLatDifferential
        • BaseSphericalDifferential
        • BoundsError
        • CIRS
        • CartesianDifferential
        • CartesianRepresentation
        • CartesianRepresentationAttribute
        • CompositeTransform
        • ConvertError
        • CoordinateAttribute
        • CoordinateFrameInfo
        • CoordinateMatchResult
        • CoordinateSearchResult
        • CoordinateTransform
        • CustomBarycentricEcliptic
        • CylindricalDifferential
        • CylindricalRepresentation
        • DifferentialAttribute
        • Distance
        • DynamicMatrixTransform
        • EarthLocation
        • EarthLocationAttribute
        • FK4
        • FK4NoETerms
        • FK5
        • FunctionTransform
        • FunctionTransformWithFiniteDifference
        • GCRS
        • GRS80GeodeticRepresentation
        • Galactic
        • GalacticLSR
        • Galactocentric
        • GenericFrame
        • GeocentricMeanEcliptic
        • GeocentricTrueEcliptic
        • HADec
        • HCRS
        • HeliocentricEclipticIAU76
        • HeliocentricMeanEcliptic
        • HeliocentricTrueEcliptic
        • ICRS
        • ITRS
        • IllegalHourError
        • IllegalHourWarning
        • IllegalMinuteError
        • IllegalMinuteWarning
        • IllegalSecondError
        • IllegalSecondWarning
        • LSR
        • LSRD
        • LSRK
        • Latitude
        • Longitude
        • NonRotationTransformationError
        • NonRotationTransformationWarning
        • PhysicsSphericalDifferential
        • PhysicsSphericalRepresentation
        • PrecessedGeocentric
        • QuantityAttribute
        • RadialDifferential
        • RadialRepresentation
        • RangeError
        • RepresentationMapping
        • SkyCoord
        • SkyCoordInfo
        • SkyOffsetFrame
        • SpectralCoord
        • SpectralQuantity
        • SphericalCosLatDifferential
        • SphericalDifferential
        • SphericalRepresentation
        • StaticMatrixTransform
        • StokesCoord
        • StokesSymbol
        • Supergalactic
        • TEME
        • TETE
        • TimeAttribute
        • TransformGraph
        • UnitSphericalCosLatDifferential
        • UnitSphericalDifferential
        • UnitSphericalRepresentation
        • UnknownSiteException
        • WGS72GeodeticRepresentation
        • WGS84GeodeticRepresentation
        • galactocentric_frame_defaults
        • solar_system_ephemeris
    • World Coordinate System (astropy.wcs)
      • Shared Python Interface for World Coordinate Systems
      • Legacy Interface
      • Supported Projections
      • Example of Imaging WCS
      • Example of Cube WCS
      • Example of a Planetary WCS
      • Loading From a FITS File
      • Subsetting and Pixel Scales
      • Header-reading relaxation constants
      • astropy.wcs History
      • Validation and Bounds checking
      • Reference/API
        • find_all_wcs
        • get_include
        • validate
        • Auxprm
        • Celprm
        • DistortionLookupTable
        • FITSFixedWarning
        • InconsistentAxisTypesError
        • InvalidCoordinateError
        • InvalidPrjParametersError
        • InvalidSubimageSpecificationError
        • InvalidTabularParametersError
        • InvalidTransformError
        • NoConvergence
        • NoSolutionError
        • NoWcsKeywordsFoundError
        • NoWcslibHeadersError
        • NonseparableSubimageCoordinateSystemError
        • Prjprm
        • SingularMatrixError
        • Sip
        • Tabprm
        • WCS
        • WCSBase
        • WcsError
        • Wcsprm
        • Wtbarr
        • add_stokes_axis_to_wcs
        • celestial_frame_to_wcs
        • fit_wcs_from_points
        • is_proj_plane_distorted
        • local_partial_pixel_derivatives
        • non_celestial_pixel_scales
        • obsgeo_to_frame
        • pixel_to_pixel
        • pixel_to_skycoord
        • proj_plane_pixel_area
        • proj_plane_pixel_scales
        • skycoord_to_pixel
        • wcs_to_celestial_frame
        • custom_frame_to_wcs_mappings
        • custom_wcs_to_frame_mappings
        • deserialize_class
        • high_level_objects_to_values
        • sanitize_slices
        • validate_physical_types
        • values_to_high_level_objects
        • wcs_info_str
        • BaseHighLevelWCS
        • BaseLowLevelWCS
        • BaseWCSWrapper
        • HighLevelWCSMixin
        • HighLevelWCSWrapper
        • SlicedLowLevelWCS
    • Models and Fitting (astropy.modeling)
      • Models
      • Compound Models
      • Model Parameters
      • Fitting
      • Using Units with Models and Fitting
      • Performance Tips
      • Extending Models
      • Extending Fitters
      • Adding support for units to models
      • JointFitter
      • Parallel Fitting
      • 1D Models
      • 2D Models
      • Physical Models
      • Polynomial Models
      • Powerlaw Models
      • Spline Models
      • Fitting a line
      • Fitting with constraints
      • Fitting Model Sets
      • Reference/API
        • bind_bounding_box
        • bind_compound_bounding_box
        • compose_models_with_units
        • custom_model
        • fix_inputs
        • is_separable
        • separability_matrix
        • CompoundModel
        • Fittable1DModel
        • Fittable2DModel
        • FittableModel
        • InputParameterError
        • Model
        • ModelDefinitionError
        • Parameter
        • ParameterError
        • CompoundBoundingBox
        • ModelBoundingBox
        • Identity
        • Mapping
        • UnitsMapping
        • parallel_fit_dask
        • DogBoxLSQFitter
        • FitInfoArrayContainer
        • Fitter
        • FittingWithOutlierRemoval
        • JointFitter
        • LMLSQFitter
        • LevMarLSQFitter
        • LinearLSQFitter
        • ModelLinearityError
        • ModelsError
        • SLSQPLSQFitter
        • SimplexLSQFitter
        • TRFLSQFitter
        • SLSQP
        • Optimization
        • Simplex
        • leastsquare
        • leastsquare_1d
        • leastsquare_2d
        • leastsquare_3d
        • is_separable
        • separability_matrix
        • AiryDisk2D
        • ArcCosine1D
        • ArcSine1D
        • ArcTangent1D
        • Box1D
        • Box2D
        • Const1D
        • Const2D
        • Cosine1D
        • Disk2D
        • Ellipse2D
        • Exponential1D
        • Gaussian1D
        • Gaussian2D
        • GeneralSersic2D
        • KingProjectedAnalytic1D
        • Linear1D
        • Logarithmic1D
        • Lorentz1D
        • Lorentz2D
        • Moffat1D
        • Moffat2D
        • Multiply
        • Planar2D
        • RedshiftScaleFactor
        • RickerWavelet1D
        • RickerWavelet2D
        • Ring2D
        • Scale
        • Sersic1D
        • Sersic2D
        • Shift
        • Sine1D
        • Tangent1D
        • Trapezoid1D
        • TrapezoidDisk2D
        • Voigt1D
        • NFW
        • BlackBody
        • Drude1D
        • Plummer1D
        • BrokenPowerLaw1D
        • ExponentialCutoffPowerLaw1D
        • LogParabola1D
        • PowerLaw1D
        • Schechter1D
        • SmoothlyBrokenPowerLaw1D
        • SIP
        • Chebyshev1D
        • Chebyshev2D
        • Hermite1D
        • Hermite2D
        • InverseSIP
        • Legendre1D
        • Legendre2D
        • OrthoPolynomialBase
        • Polynomial1D
        • Polynomial2D
        • PolynomialModel
        • AffineTransformation2D
        • Conic
        • Cylindrical
        • HEALPix
        • Pix2SkyProjection
        • Projection
        • PseudoConic
        • PseudoCylindrical
        • QuadCube
        • Sky2PixProjection
        • Zenithal
        • Pix2Sky_ZenithalPerspective
        • Pix2Sky_AZP
        • Pix2Sky_SlantZenithalPerspective
        • Pix2Sky_SZP
        • Pix2Sky_Gnomonic
        • Pix2Sky_TAN
        • Pix2Sky_Stereographic
        • Pix2Sky_STG
        • Pix2Sky_SlantOrthographic
        • Pix2Sky_SIN
        • Pix2Sky_ZenithalEquidistant
        • Pix2Sky_ARC
        • Pix2Sky_ZenithalEqualArea
        • Pix2Sky_ZEA
        • Pix2Sky_Airy
        • Pix2Sky_AIR
        • Pix2Sky_CylindricalPerspective
        • Pix2Sky_CYP
        • Pix2Sky_CylindricalEqualArea
        • Pix2Sky_CEA
        • Pix2Sky_PlateCarree
        • Pix2Sky_CAR
        • Pix2Sky_Mercator
        • Pix2Sky_MER
        • Pix2Sky_SansonFlamsteed
        • Pix2Sky_SFL
        • Pix2Sky_Parabolic
        • Pix2Sky_PAR
        • Pix2Sky_Molleweide
        • Pix2Sky_MOL
        • Pix2Sky_HammerAitoff
        • Pix2Sky_AIT
        • Pix2Sky_ConicPerspective
        • Pix2Sky_COP
        • Pix2Sky_ConicEqualArea
        • Pix2Sky_COE
        • Pix2Sky_ConicEquidistant
        • Pix2Sky_COD
        • Pix2Sky_ConicOrthomorphic
        • Pix2Sky_COO
        • Pix2Sky_BonneEqualArea
        • Pix2Sky_BON
        • Pix2Sky_Polyconic
        • Pix2Sky_PCO
        • Pix2Sky_TangentialSphericalCube
        • Pix2Sky_TSC
        • Pix2Sky_COBEQuadSphericalCube
        • Pix2Sky_CSC
        • Pix2Sky_QuadSphericalCube
        • Pix2Sky_QSC
        • Pix2Sky_HEALPix
        • Pix2Sky_HPX
        • Pix2Sky_HEALPixPolar
        • Pix2Sky_XPH
        • Sky2Pix_ZenithalPerspective
        • Sky2Pix_AZP
        • Sky2Pix_SlantZenithalPerspective
        • Sky2Pix_SZP
        • Sky2Pix_Gnomonic
        • Sky2Pix_TAN
        • Sky2Pix_Stereographic
        • Sky2Pix_STG
        • Sky2Pix_SlantOrthographic
        • Sky2Pix_SIN
        • Sky2Pix_ZenithalEquidistant
        • Sky2Pix_ARC
        • Sky2Pix_ZenithalEqualArea
        • Sky2Pix_ZEA
        • Sky2Pix_Airy
        • Sky2Pix_AIR
        • Sky2Pix_CylindricalPerspective
        • Sky2Pix_CYP
        • Sky2Pix_CylindricalEqualArea
        • Sky2Pix_CEA
        • Sky2Pix_PlateCarree
        • Sky2Pix_CAR
        • Sky2Pix_Mercator
        • Sky2Pix_MER
        • Sky2Pix_SansonFlamsteed
        • Sky2Pix_SFL
        • Sky2Pix_Parabolic
        • Sky2Pix_PAR
        • Sky2Pix_Molleweide
        • Sky2Pix_MOL
        • Sky2Pix_HammerAitoff
        • Sky2Pix_AIT
        • Sky2Pix_ConicPerspective
        • Sky2Pix_COP
        • Sky2Pix_ConicEqualArea
        • Sky2Pix_COE
        • Sky2Pix_ConicEquidistant
        • Sky2Pix_COD
        • Sky2Pix_ConicOrthomorphic
        • Sky2Pix_COO
        • Sky2Pix_BonneEqualArea
        • Sky2Pix_BON
        • Sky2Pix_Polyconic
        • Sky2Pix_PCO
        • Sky2Pix_TangentialSphericalCube
        • Sky2Pix_TSC
        • Sky2Pix_COBEQuadSphericalCube
        • Sky2Pix_CSC
        • Sky2Pix_QuadSphericalCube
        • Sky2Pix_QSC
        • Sky2Pix_HEALPix
        • Sky2Pix_HPX
        • Sky2Pix_HEALPixPolar
        • Sky2Pix_XPH
        • EulerAngleRotation
        • RotateCelestial2Native
        • RotateNative2Celestial
        • Rotation2D
        • RotationSequence3D
        • SphericalRotationSequence
        • Spline1D
        • SplineExactKnotsFitter
        • SplineInterpolateFitter
        • SplineSmoothingFitter
        • SplineSplrepFitter
        • tabular_model
        • Tabular1D
        • Tabular2D
    • Uncertainties and Distributions (astropy.uncertainty)
      • normal
      • poisson
      • uniform
      • Distribution
    • Overview of Astropy File I/O
    • High-level Unified File I/O
      • Image Data
      • Table Data
        • Text (CSV, fixed-width, HTML, and specialized)
        • FITS
        • HDF5
        • Parquet
        • VO Tables
    • FITS File Handling (astropy.io.fits)
      • FITS Headers
      • Image Data
      • Table Data
      • Verification
      • Less Familiar Objects
      • Executable Scripts
      • Miscellaneous Features
      • Obtaining subsets from cloud-hosted FITS files
      • astropy.io.fits FAQ
      • Header Interface Transition Guide
      • astropy.io.fits History
      • Reference/API
        • File Handling and Convenience Functions
        • HDU Lists
        • Header Data Unit
        • Headers
        • Cards
        • Tables
        • Images
        • Differs
        • Verification Options
        • Tiled Compression
    • Text Tables (astropy.io.ascii)
      • Reading Tables
      • Writing Tables
      • ECSV Format
      • Fixed-Width Gallery
      • Fast ASCII I/O
      • Base Class Elements
      • Extension Reader Classes
      • Reference/API
        • convert_numpy
        • get_read_trace
        • get_reader
        • get_writer
        • read
        • set_guess
        • write
        • AASTex
        • AllType
        • BaseData
        • BaseHeader
        • BaseInputter
        • BaseOutputter
        • BaseReader
        • BaseSplitter
        • Basic
        • BasicData
        • BasicHeader
        • Cds
        • Column
        • CommentedHeader
        • Conf
        • ContinuationLinesInputter
        • Csv
        • Daophot
        • DefaultSplitter
        • Ecsv
        • FastBasic
        • FastCommentedHeader
        • FastCsv
        • FastNoHeader
        • FastRdb
        • FastTab
        • FixedWidth
        • FixedWidthData
        • FixedWidthHeader
        • FixedWidthNoHeader
        • FixedWidthSplitter
        • FixedWidthTwoLine
        • FloatType
        • HTML
        • InconsistentTableError
        • IntType
        • Ipac
        • Latex
        • Mesa
        • Mrt
        • NoHeader
        • NoType
        • NumType
        • ParameterError
        • QDP
        • RST
        • Rdb
        • SExtractor
        • StrType
        • Tab
        • TableOutputter
        • Tdat
        • WhitespaceSplitter
    • VOTable Handling (astropy.io.votable)
      • Table element
      • COOSYS element
      • Reading and writing VO model annotations (MIVOT)
      • Reference/API
        • from_table
        • is_votable
        • parse
        • parse_single_table
        • validate
        • writeto
        • Conf
        • CooSys
        • Element
        • Field
        • FieldRef
        • Group
        • Info
        • Link
        • MivotBlock
        • Param
        • ParamRef
        • Resource
        • TableElement
        • TimeSys
        • VOTableFile
        • Values
        • get_converter
        • table_column_to_votable_datatype
        • Converter
        • check_ucd
        • parse_ucd
        • coerce_range_list_param
        • convert_to_writable_filelike
        • make_validation_report
        • check_anyuri
        • check_id
        • check_mime_content_type
        • check_token
        • fix_id
        • validate_schema
        • add_data_origin_info
        • extract_data_origin
        • DataOrigin
        • DatasetOrigin
        • QueryOrigin
      • astropy.io.votable.exceptions
    • ECSV, HDF5, Parquet, PyArrow CSV, YAML (astropy.io.misc)
      • Reference/API
        • fnpickle
        • fnunpickle
        • read_ecsv
        • register_ecsv_table
        • write_ecsv
        • ColumnECSV
        • ECSVEngine
        • ECSVEngineIoAscii
        • ECSVEnginePandas
        • ECSVEnginePyArrow
        • ECSVHeader
        • read_table_hdf5
        • write_table_hdf5
        • convert_pa_table_to_astropy_table
        • read_csv
        • dump
        • load
        • load_all
        • AstropyDumper
        • AstropyLoader
    • Cosmological Calculations (astropy.cosmology)
      • Included Cosmology Realizations
        • available
        • WMAP1
        • WMAP3
        • WMAP5
        • WMAP7
        • WMAP9
        • Planck13
        • Planck15
        • Planck18
      • Units and Equivalencies
        • dimensionless_redshift
        • redshift_distance
        • redshift_hubble
        • redshift_temperature
        • with_H0
        • with_redshift
      • Cosmology I/O & Convert
        • Cosmology I/O Details
        • Built-in Cosmology To/From Formats
        • Custom Cosmology I/O formats
        • CosmologyFromFormat
        • CosmologyRead
        • CosmologyToFormat
        • CosmologyWrite
      • Traits
        • BaryonComponent
        • CriticalDensity
        • CurvatureComponent
        • DarkEnergyComponent
        • DarkMatterComponent
        • HubbleParameter
        • MatterComponent
        • NeutrinoComponent
        • PhotonComponent
        • ScaleFactor
        • TemperatureCMB
        • TotalComponent
      • For Developers
      • Reference/API
        • z_at_value
        • cosmology_equal
        • Cosmology
        • CosmologyError
        • FlatCosmologyMixin
        • FLRW
        • FlatFLRWMixin
        • LambdaCDM
        • FlatLambdaCDM
        • wCDM
        • FlatwCDM
        • w0waCDM
        • Flatw0waCDM
        • w0wzCDM
        • Flatw0wzCDM
        • wpwaCDM
        • FlatwpwaCDM
        • Parameter
        • default_cosmology
    • Convolution and Filtering (astropy.convolution)
      • Using the Convolution Functions
      • Convolution Kernels
      • Convolving with Unnormalized Kernels
      • Reference/API
        • convolve
        • convolve_fft
        • convolve_models
        • convolve_models_fft
        • discretize_model
        • interpolate_replace_nans
        • kernel_arithmetics
        • AiryDisk2DKernel
        • Box1DKernel
        • Box2DKernel
        • CustomKernel
        • Gaussian1DKernel
        • Gaussian2DKernel
        • Kernel
        • Kernel1D
        • Kernel2D
        • KernelArithmeticError
        • KernelError
        • KernelSizeError
        • Model1DKernel
        • Model2DKernel
        • Moffat2DKernel
        • RickerWavelet1DKernel
        • RickerWavelet2DKernel
        • Ring2DKernel
        • Tophat2DKernel
        • Trapezoid1DKernel
        • TrapezoidDisk2DKernel
    • IERS data access (astropy.utils.iers)
    • Data Visualization (astropy.visualization)
      • Plotting Astropy objects in Matplotlib
      • Making plots with world coordinates (WCSAxes)
        • Initializing axes with world coordinates
        • Plotting images and contours
        • Ticks, tick labels, and grid lines
        • Overplotting markers and artists
        • Overlaying coordinate systems
        • Slicing Multidimensional Data
        • Controlling Axes
        • Initializing WCSAxes with custom transforms
        • Using a custom frame
        • add_beam
        • add_scalebar
        • custom_ucd_coord_meta_mapping
        • Conf
        • CoordinateHelper
        • CoordinatesMap
        • Quadrangle
        • SphericalCircle
        • WCSAxes
        • WCSAxesSubplot
        • BaseFrame
        • EllipticalFrame
        • RectangularFrame
        • RectangularFrame1D
        • Spine
      • Image stretching and normalization
      • Choosing Histogram Bins
      • Creating color RGB images
      • Reference/API
        • hist
        • imshow_norm
        • imshow_simple_norm
        • make_lupton_rgb
        • make_rgb
        • quantity_support
        • simple_norm
        • time_support
        • AsinhStretch
        • AsymmetricPercentileInterval
        • BaseInterval
        • BaseStretch
        • BaseTransform
        • CompositeStretch
        • CompositeTransform
        • ContrastBiasStretch
        • HistEqStretch
        • ImageNormalize
        • LinearStretch
        • LogStretch
        • LuptonAsinhStretch
        • LuptonAsinhZscaleStretch
        • ManualInterval
        • MinMaxInterval
        • MplQuantityConverter
        • PercentileInterval
        • PowerDistStretch
        • PowerStretch
        • SimpleNorm
        • SinhStretch
        • SqrtStretch
        • SquaredStretch
        • SymmetricInterval
        • ZScaleInterval
        • imshow_norm
        • imshow_simple_norm
        • simple_norm
        • ImageNormalize
        • SimpleNorm
    • Astrostatistics Tools (astropy.stats)
      • Robust Statistical Estimators
        • sigma_clip
        • sigma_clipped_stats
        • SigmaClip
        • SigmaClippedStats
        • biweight_location
        • biweight_midcorrelation
        • biweight_midcovariance
        • biweight_midvariance
        • biweight_scale
      • Circular Statistics
        • circcorrcoef
        • circmean
        • circmoment
        • circstd
        • circvar
        • rayleightest
        • vonmisesmle
        • vtest
      • Ripley’s K Function Estimators
      • Reference/API
        • binned_binom_proportion
        • binom_conf_interval
        • bootstrap
        • cdf_from_intervals
        • fold_intervals
        • histogram_intervals
        • interval_overlap_length
        • kuiper
        • kuiper_false_positive_probability
        • kuiper_two
        • mad_std
        • median_absolute_deviation
        • poisson_conf_interval
        • signal_to_noise_oir_ccd
        • biweight_location
        • biweight_midcorrelation
        • biweight_midcovariance
        • biweight_midvariance
        • biweight_scale
        • sigma_clip
        • sigma_clipped_stats
        • jackknife_resampling
        • jackknife_stats
        • circcorrcoef
        • circmean
        • circmoment
        • circstd
        • circvar
        • rayleightest
        • vonmisesmle
        • vtest
        • bayesian_blocks
        • calculate_bin_edges
        • freedman_bin_width
        • histogram
        • knuth_bin_width
        • scott_bin_width
        • akaike_info_criterion
        • akaike_info_criterion_lsq
        • bayesian_info_criterion
        • bayesian_info_criterion_lsq
        • SigmaClip
        • SigmaClippedStats
        • Events
        • FitnessFunc
        • PointMeasures
        • RegularEvents
        • RipleysKEstimator
    • Masked Values and Quantities (astropy.utils.masked)
      • combine_masks
      • get_data_and_mask
      • MaskableShapedLikeNDArray
      • Masked
      • MaskedNDArray
      • bincount
      • broadcast_arrays
      • broadcast_to
      • choose
      • copyto
      • count_nonzero
      • full_like
      • insert
      • interp
      • lexsort
      • nanargmax
      • nanargmin
      • nancumprod
      • nancumsum
      • nanmax
      • nanmean
      • nanmedian
      • nanmin
      • nanpercentile
      • nanprod
      • nanquantile
      • nanstd
      • nansum
      • nanvar
      • ones_like
      • piecewise
      • place
      • put
      • select
      • zeros_like
    • SAMP (Simple Application Messaging Protocol) (astropy.samp)
      • Starting and Stopping a SAMP Hub Server
      • Sending and Receiving Tables and Images over SAMP
      • Communication between Integrated Clients Objects
      • Embedding a SAMP Hub in a GUI
      • Reference/API
        • safe_xmlrpc_loads
        • Conf
        • SAMPClient
        • SAMPClientError
        • SAMPHubError
        • SAMPHubProxy
        • SAMPHubServer
        • SAMPIntegratedClient
        • SAMPMsgReplierWrapper
        • SAMPProxyError
        • SAMPWarning
        • SAMPXXEServerProxy
        • WebProfileDialog
    • Configuration System (astropy.config)
      • Astropy’s Default Configuration File
      • Reference/API
        • create_config_file
        • generate_config
        • get_cache_dir
        • get_cache_dir_path
        • get_config
        • get_config_dir
        • get_config_dir_path
        • reload_config
        • temporary_cache_dir_path
        • temporary_config_dir_path
        • ConfigItem
        • ConfigNamespace
        • InvalidConfigurationItemWarning
        • set_temp_cache
        • set_temp_config
    • I/O Registry (astropy.io.registry)
      • Reference/API
        • delay_doc_updates
        • get_formats
        • get_reader
        • get_writer
        • identify_format
        • read
        • register_identifier
        • register_reader
        • register_writer
        • unregister_identifier
        • unregister_reader
        • unregister_writer
        • write
        • UnifiedIORegistry
        • UnifiedInputRegistry
        • UnifiedOutputRegistry
        • UnifiedReadWrite
        • UnifiedReadWriteMethod
        • IORegistryError
    • I/O Typing (astropy.io.typing)
      • ReadableFileLike
      • WriteableFileLike
    • Logging system
      • AstropyLogger
      • Conf
      • LoggingError
    • Python warnings system
    • Astropy Core Package Utilities (astropy.utils)
      • Downloadable Data Management (astropy.utils.data)
      • Reference/API
        • make_function_with_signature
        • HomogeneousList
        • color_print
        • human_file_size
        • human_time
        • isatty
        • print_code_line
        • terminal_size
        • ProgressBar
        • ProgressBarOrSpinner
        • Spinner
        • data_info_factory
        • dtype_info_name
        • BaseColumnInfo
        • DataInfo
        • MixinInfo
        • ParentDtypeInfo
        • deprecated
        • deprecated_attribute
        • deprecated_renamed_argument
        • format_doc
        • classproperty
        • lazyproperty
        • sharedmethod
        • diff_values
        • report_diff_values
        • where_not_allclose
        • AstropyBackwardsIncompatibleChangeWarning
        • AstropyDeprecationWarning
        • AstropyPendingDeprecationWarning
        • AstropyUserWarning
        • AstropyWarning
        • DuplicateRepresentationWarning
        • Conf
        • IERS
        • IERSDegradedAccuracyWarning
        • IERSRangeError
        • IERSStaleWarning
        • IERSWarning
        • IERS_A
        • IERS_Auto
        • IERS_B
        • LeapSeconds
        • earth_orientation_table
        • find_current_module
        • isinstancemethod
        • minversion
        • resolve_name
        • enable_merge_strategies
        • merge
        • common_dtype
        • MetaAttribute
        • MetaData
        • MergeNpConcatenate
        • MergePlus
        • MergeStrategy
        • MergeConflictError
        • MergeConflictWarning
        • dtype_bytes_or_chars
        • find_api_page
        • format_exception
        • indent
        • isiterable
        • online_help
        • silence
        • JsonCustomEncoder
        • NumpyRNGContext
        • lex
        • yacc
        • ThreadSafeParser
        • ScienceState
        • check_broadcast
        • simplify_basic_index
        • unbroadcast
        • IncompatibleShapeError
        • NDArrayShapeMethods
        • ShapedLikeNDArray
        • system_info
        • cache_contents
        • cache_total_size
        • check_download_cache
        • check_free_space_in_dir
        • clear_download_cache
        • compute_hash
        • download_file
        • download_files_in_parallel
        • export_download_cache
        • get_cached_urls
        • get_file_contents
        • get_free_space_in_dir
        • get_pkg_data_contents
        • get_pkg_data_filename
        • get_pkg_data_filenames
        • get_pkg_data_fileobj
        • get_pkg_data_fileobjs
        • get_pkg_data_path
        • get_readable_fileobj
        • import_download_cache
        • import_file_to_cache
        • is_url
        • is_url_in_cache
        • CacheDamaged
        • CacheMissingWarning
        • Conf
        • check_anyuri
        • check_id
        • check_mime_content_type
        • check_token
        • fix_id
        • get_xml_encoding
        • get_xml_iterator
        • xml_readlines
        • unescape_all
        • validate_schema
        • XMLWriter
    • Environment variables
    • Astropy Glossary
  • Contributing
    • Contributing Quickstart
    • Contributing Code: a Worked Example
    • Development Details
    • Coding Guidelines
    • Testing Guidelines
    • Documentation Guidelines
    • Astropy Narrative Style Guide
    • Git Resources
    • Command-Line Scripts
    • C or Cython Extensions
    • Maintaining astropy and affiliated packages
      • How to create and maintain a Python package using the Astropy template
      • Workflow for Maintainers
      • Managing Dependencies
      • Release procedure for the astropy core package
      • Astropy Testing Tools
        • assert_follows_unicode_guidelines
        • assert_quantity_allclose
        • check_pickling_recovery
        • generic_recursive_equality_test
        • pickle_protocol
        • TestRunner
        • TestRunnerBase
  • Project Details
    • What’s New
      • What’s New in Astropy 8.1?
    • Full Changelog
    • LTS Backport Policy
    • Known Issues
    • Authors and Credits
    • Impact and Health
    • Licenses
  • Getting Started

Getting Started#

What’s New in Astropy 8.1?

  • Installation
  • Importing astropy and Sub-packages
  • Getting Started with Sub-packages
  • Tutorials

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