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grib2

package module

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Versions in this module

v1

v1.2.0

Oct 10, 2026

Changes in this version

+ type BilinearWeights struct

+ Index [4]int

+ Outside bool

+ XFrac float64

+ YFrac float64

+ func (w BilinearWeights) Interpolate(values []float64) (float64, error)

+ func (w BilinearWeights) NearestCorner() int

+ type Sampler struct

+ func NewSampler(f *Field) (*Sampler, error)

+ func (s *Sampler) Matches(f *Field) bool

+ func (s *Sampler) Weights(lat, lon float64) (BilinearWeights, error)

v1.1.1

Apr 9, 2026

v1.1.0

Apr 9, 2026

v1.0.4

Apr 9, 2026

v1.0.3

Apr 9, 2026

v1.0.2

Apr 9, 2026

v1.0.1

Apr 9, 2026

Changes in this version

type Field

+ func (f *Field) SurfaceLevel() (float64, error)

+ func (f *Field) SurfaceLevelHPa() (float64, error)

+ func (f *Field) SurfaceType() (uint8, error)

v1.0.0

Apr 8, 2026

Changes in this version

+ var ErrInvalidEndSection = errors.New("grib2: invalid end section (expected 7777)")

+ var ErrNotEdition2 = errors.New("grib2: not GRIB edition 2")

+ var ErrNotGRIB = errors.New("grib2: not a GRIB file (missing GRIB magic)")

+ var ErrTruncated = errors.New("grib2: message truncated")

+ func CentreName(c uint16) string

+ func DataRepresentationTemplateName(n uint16) string

+ func DataTypeName(t uint8) string

+ func DisciplineName(d uint8) string

+ func GridDefinitionTemplateName(n uint16) string

+ func ParameterCategoryName(discipline, category uint8) string

+ func ParameterName(discipline, category, number uint8) string

+ func ParameterUnit(discipline, category, number uint8) string

+ func ProductDefinitionTemplateName(n uint16) string

+ func ProductionStatusName(s uint8) string

+ func ReadSection8(r io.Reader) error

+ func ReferenceTimeName(t uint8) string

+ func SurfaceTypeName(t uint8) string

+ func UnpackCCSDS(data []byte, tmpl Template542, numValues uint32) ([]float64, error)

+ func UnpackComplex(data []byte, tmpl52 Template52, numValues uint32, orderOfSpatialDiff uint8, ...) ([]float64, error)

+ func UnpackComplexWithSubstitution(data []byte, tmpl52 Template52, numValues uint32, orderOfSpatialDiff uint8, ...) ([]float64, error)

+ func UnpackIEEE(data []byte, tmpl Template54, numValues uint32) ([]float64, error)

+ func UnpackJPEG2000(data []byte, tmpl Template540, numValues uint32) ([]float64, error)

+ func UnpackPNG(data []byte, tmpl Template50, numValues uint32) ([]float64, error)

+ func UnpackRunLength(data []byte, tmpl Template5200, numValues uint32, missingValue float64) ([]float64, error)

+ func UnpackSimple(data []byte, tmpl Template50, numValues uint32) ([]float64, error)

+ func WriteMessage(w io.Writer, msg *Message) error

+ func WriteSection0(w io.Writer, s Section0) error

+ func WriteSection1(w io.Writer, s Section1) error

+ func WriteSection2(w io.Writer, s Section2) error

+ func WriteSection3(w io.Writer, s Section3) error

+ func WriteSection4(w io.Writer, s Section4) error

+ func WriteSection5(w io.Writer, s Section5) error

+ func WriteSection6(w io.Writer, s Section6) error

+ func WriteSection7(w io.Writer, s Section7) error

+ func WriteSection8(w io.Writer) error

+ type DataRepresentationTemplate interface

+ TemplateNumber func() uint16

+ type Decoder struct

+ func NewDecoder(r io.Reader) *Decoder

+ func (d *Decoder) Decode() (*Message, error)

+ type Field struct

+ Section3 Section3

+ Section4 Section4

+ Section5 Section5

+ Section6 Section6

+ Section7 Section7

+ func (f *Field) BilinearValue(lat, lon float64) (float64, error)

+ func (f *Field) GridCoordinates() (lats, lons []float64, err error)

+ func (f *Field) NearestValue(lat, lon float64) (value float64, idx int, nearLat, nearLon float64, err error)

+ func (f *Field) Values() ([]float64, error)

+ type GridDefinitionTemplate interface

+ TemplateNumber func() uint16

+ type Message struct

+ Fields []Field

+ Section0 Section0

+ Section1 Section1

+ Section2 *Section2

+ func ReadMessage(r io.Reader) (*Message, error)

+ type ProductDefinitionTemplate interface

+ TemplateNumber func() uint16

+ type RawDataRepTemplate struct

+ Data []byte

+ Number uint16

+ func (t *RawDataRepTemplate) TemplateNumber() uint16

+ type RawGridTemplate struct

+ Data []byte

+ Number uint16

+ func (t *RawGridTemplate) TemplateNumber() uint16

+ type RawProductTemplate struct

+ Data []byte

+ Number uint16

+ func (t *RawProductTemplate) TemplateNumber() uint16

+ type Section0 struct

+ Discipline uint8

+ Edition uint8

+ Reserved [2]byte

+ TotalLength uint64

+ func ReadSection0(r io.Reader) (Section0, error)

+ func (s Section0) String() string

+ type Section1 struct

+ Centre uint16

+ Day uint8

+ Hour uint8

+ Length uint32

+ LocalTablesVersion uint8

+ MasterTablesVersion uint8

+ Minute uint8

+ Month uint8

+ ProductionStatus uint8

+ Second uint8

+ SignificanceOfReferenceTime uint8

+ SubCentre uint16

+ TypeOfData uint8

+ Year uint16

+ func ReadSection1(r io.Reader) (Section1, error)

+ func (s *Section1) ReferenceTime() time.Time

+ func (s Section1) String() string

+ type Section2 struct

+ Data []byte

+ Length uint32

+ func ReadSection2(r io.Reader) (Section2, error)

+ type Section3 struct

+ InterpretationOfPoints uint8

+ Length uint32

+ NumberOfDataPoints uint32

+ OctetsForNumberOfPoints uint8

+ OptionalPointNumbers []byte

+ Source uint8

+ Template GridDefinitionTemplate

+ TemplateNumber uint16

+ func ReadSection3(r io.Reader) (Section3, error)

+ func (s Section3) String() string

+ type Section4 struct

+ CoordinateValues []byte

+ Length uint32

+ NV uint16

+ Template ProductDefinitionTemplate

+ TemplateNumber uint16

+ func ReadSection4(r io.Reader) (Section4, error)

+ func (s Section4) String() string

+ type Section5 struct

+ Length uint32

+ NumberOfValues uint32

+ Template DataRepresentationTemplate

+ TemplateNumber uint16

+ func ReadSection5(r io.Reader) (Section5, error)

+ func (s Section5) String() string

+ type Section6 struct

+ Bitmap []byte

+ Indicator uint8

+ Length uint32

+ func ReadSection6(r io.Reader) (Section6, error)

+ func (s *Section6) HasBitmap() bool

+ type Section7 struct

+ Data []byte

+ Length uint32

+ func ReadSection7(r io.Reader) (Section7, error)

+ type Template30 struct

+ BasicAngle uint32

+ IDirectionIncrement uint32

+ JDirectionIncrement uint32

+ LatitudeOfFirstGridPoint int32

+ LatitudeOfLastGridPoint int32

+ LongitudeOfFirstGridPoint int32

+ LongitudeOfLastGridPoint int32

+ Ni uint32

+ Nj uint32

+ ResolutionAndComponentFlags uint8

+ ScaleFactorOfEarthMajorAxis uint8

+ ScaleFactorOfEarthMinorAxis uint8

+ ScaleFactorOfRadiusOfSphericalEarth uint8

+ ScaledValueOfEarthMajorAxis uint32

+ ScaledValueOfEarthMinorAxis uint32

+ ScaledValueOfRadiusOfSphericalEarth uint32

+ ScanningMode uint8

+ ShapeOfEarth uint8

+ SubdivisionsOfBasicAngle uint32

+ func (Template30) TemplateNumber() uint16

+ type Template31 struct

+ AngleOfRotation uint32

+ BasicAngle uint32

+ IDirectionIncrement uint32

+ JDirectionIncrement uint32

+ LatitudeOfFirstGridPoint int32

+ LatitudeOfLastGridPoint int32

+ LatitudeOfSouthernPole int32

+ LongitudeOfFirstGridPoint int32

+ LongitudeOfLastGridPoint int32

+ LongitudeOfSouthernPole int32

+ Ni uint32

+ Nj uint32

+ ResolutionAndComponentFlags uint8

+ ScaleFactorOfEarthMajorAxis uint8

+ ScaleFactorOfEarthMinorAxis uint8

+ ScaleFactorOfRadiusOfSphericalEarth uint8

+ ScaledValueOfEarthMajorAxis uint32

+ ScaledValueOfEarthMinorAxis uint32

+ ScaledValueOfRadiusOfSphericalEarth uint32

+ ScanningMode uint8

+ ShapeOfEarth uint8

+ SubdivisionsOfBasicAngle uint32

+ func (Template31) TemplateNumber() uint16

+ type Template310 struct

+ Di uint32

+ Dj uint32

+ LaD int32

+ LatitudeOfFirstGridPoint int32

+ LatitudeOfLastGridPoint int32

+ LongitudeOfFirstGridPoint int32

+ LongitudeOfLastGridPoint int32

+ Ni uint32

+ Nj uint32

+ OrientationOfTheGrid uint32

+ ResolutionAndComponentFlags uint8

+ ScaleFactorOfEarthMajorAxis uint8

+ ScaleFactorOfEarthMinorAxis uint8

+ ScaleFactorOfRadiusOfSphericalEarth uint8

+ ScaledValueOfEarthMajorAxis uint32

+ ScaledValueOfEarthMinorAxis uint32

+ ScaledValueOfRadiusOfSphericalEarth uint32

+ ScanningMode uint8

+ ShapeOfEarth uint8

+ func (Template310) TemplateNumber() uint16

+ type Template320 struct

+ Dx uint32

+ Dy uint32

+ LaD int32

+ LatitudeOfFirstGridPoint int32

+ LongitudeOfFirstGridPoint int32

+ Nx uint32

+ Ny uint32

+ OrientationOfTheGrid int32

+ ProjectionCentreFlag uint8

+ ResolutionAndComponentFlags uint8

+ ScaleFactorOfEarthMajorAxis uint8

+ ScaleFactorOfEarthMinorAxis uint8

+ ScaleFactorOfRadiusOfSphericalEarth uint8

+ ScaledValueOfEarthMajorAxis uint32

+ ScaledValueOfEarthMinorAxis uint32

+ ScaledValueOfRadiusOfSphericalEarth uint32

+ ScanningMode uint8

+ ShapeOfEarth uint8

+ func (Template320) TemplateNumber() uint16

+ type Template330 struct

+ Dx uint32

+ Dy uint32

+ LaD int32

+ Latin1 int32

+ Latin2 int32

+ LatitudeOfFirstGridPoint int32

+ LatitudeOfSouthernPole int32

+ LoV int32

+ LongitudeOfFirstGridPoint int32

+ LongitudeOfSouthernPole int32

+ Nx uint32

+ Ny uint32

+ ProjectionCentreFlag uint8

+ ResolutionAndComponentFlags uint8

+ ScaleFactorOfEarthMajorAxis uint8

+ ScaleFactorOfEarthMinorAxis uint8

+ ScaleFactorOfRadiusOfSphericalEarth uint8

+ ScaledValueOfEarthMajorAxis uint32

+ ScaledValueOfEarthMinorAxis uint32

+ ScaledValueOfRadiusOfSphericalEarth uint32

+ ScanningMode uint8

+ ShapeOfEarth uint8

+ func (Template330) TemplateNumber() uint16

+ type Template340 struct

+ BasicAngle uint32

+ IDirectionIncrement uint32

+ LatitudeOfFirstGridPoint int32

+ LatitudeOfLastGridPoint int32

+ LongitudeOfFirstGridPoint int32

+ LongitudeOfLastGridPoint int32

+ N uint32

+ Ni uint32

+ Nj uint32

+ ResolutionAndComponentFlags uint8

+ ScaleFactorOfEarthMajorAxis uint8

+ ScaleFactorOfEarthMinorAxis uint8

+ ScaleFactorOfRadiusOfSphericalEarth uint8

+ ScaledValueOfEarthMajorAxis uint32

+ ScaledValueOfEarthMinorAxis uint32

+ ScaledValueOfRadiusOfSphericalEarth uint32

+ ScanningMode uint8

+ ShapeOfEarth uint8

+ SubdivisionsOfBasicAngle uint32

+ func (Template340) TemplateNumber() uint16

+ type Template390 struct

+ Dx uint32

+ Dy uint32

+ LatitudeOfSubSatellitePoint int32

+ LongitudeOfSubSatellitePoint int32

+ Nr uint32

+ Nx uint32

+ Ny uint32

+ OrientationOfTheGrid int32

+ ResolutionAndComponentFlags uint8

+ ScaleFactorOfEarthMajorAxis uint8

+ ScaleFactorOfEarthMinorAxis uint8

+ ScaleFactorOfRadiusOfSphericalEarth uint8

+ ScaledValueOfEarthMajorAxis uint32

+ ScaledValueOfEarthMinorAxis uint32

+ ScaledValueOfRadiusOfSphericalEarth uint32

+ ScanningMode uint8

+ ShapeOfEarth uint8

+ Xo uint32

+ Xp uint32

+ Yo uint32

+ Yp uint32

+ func (Template390) TemplateNumber() uint16

+ type Template40 struct

+ BackgroundProcess uint8

+ ForecastTime int32

+ GeneratingProcessID uint8

+ HoursAfterCutoff uint16

+ IndicatorOfUnitOfTimeRange uint8

+ MinutesAfterCutoff uint8

+ ParameterCategory uint8

+ ParameterNumber uint8

+ ScaleFactorOfFirstSurface int8

+ ScaleFactorOfSecondSurface int8

+ ScaledValueOfFirstSurface uint32

+ ScaledValueOfSecondSurface uint32

+ TypeOfFirstFixedSurface uint8

+ TypeOfGeneratingProcess uint8

+ TypeOfSecondFixedSurface uint8

+ func (Template40) TemplateNumber() uint16

+ type Template41 struct

+ NumberOfForecastsInEnsemble uint8

+ PerturbationNumber uint8

+ TypeOfEnsembleForecast uint8

+ func (Template41) TemplateNumber() uint16

+ type Template411 struct

+ DayOfEndOfInterval uint8

+ HourOfEndOfInterval uint8

+ MinuteOfEndOfInterval uint8

+ MonthOfEndOfInterval uint8

+ NumberOfForecastsInEnsemble uint8

+ NumberOfMissingInStatisticalProcess uint32

+ NumberOfTimeRangeSpecs uint8

+ PerturbationNumber uint8

+ SecondOfEndOfInterval uint8

+ TimeRangeSpecs []TimeRangeSpec

+ TypeOfEnsembleForecast uint8

+ YearOfEndOfInterval uint16

+ func (Template411) TemplateNumber() uint16

+ type Template412 struct

+ DayOfEndOfInterval uint8

+ DerivedForecast uint8

+ HourOfEndOfInterval uint8

+ MinuteOfEndOfInterval uint8

+ MonthOfEndOfInterval uint8

+ NumberOfForecastsInEnsemble uint8

+ NumberOfMissingInStatisticalProcess uint32

+ NumberOfTimeRangeSpecs uint8

+ SecondOfEndOfInterval uint8

+ TimeRangeSpecs []TimeRangeSpec

+ YearOfEndOfInterval uint16

+ func (Template412) TemplateNumber() uint16

+ type Template42 struct

+ DerivedForecast uint8

+ NumberOfForecastsInEnsemble uint8

+ func (Template42) TemplateNumber() uint16

+ type Template48 struct

+ DayOfEndOfInterval uint8

+ HourOfEndOfInterval uint8

+ MinuteOfEndOfInterval uint8

+ MonthOfEndOfInterval uint8

+ NumberOfMissingInStatisticalProcess uint32

+ NumberOfTimeRangeSpecs uint8

+ SecondOfEndOfInterval uint8

+ TimeRangeSpecs []TimeRangeSpec

+ YearOfEndOfInterval uint16

+ func (Template48) TemplateNumber() uint16

+ type Template50 struct

+ BinaryScaleFactor int16

+ BitsPerValue uint8

+ DecimalScaleFactor int16

+ ReferenceValue float32

+ TypeOfOriginalFieldValues uint8

+ func PackPNG(values []float64, bitsPerValue uint8, width, height int) ([]byte, Template50, error)

+ func PackSimple(values []float64, bitsPerValue uint8) ([]byte, Template50, error)

+ func (Template50) TemplateNumber() uint16

+ type Template52 struct

+ GroupSplittingMethod uint8

+ LengthIncrementForGroupLengths uint8

+ MissingValueManagement uint8

+ NumberOfBitsForGroupWidths uint8

+ NumberOfBitsForScaledGroupLengths uint8

+ NumberOfGroups uint32

+ PrimaryMissingValueSubstitute uint32

+ ReferenceForGroupLengths uint32

+ ReferenceForGroupWidths uint8

+ SecondaryMissingValueSubstitute uint32

+ TrueLengthOfLastGroup uint32

+ func PackComplex(values []float64, bitsPerValue uint8) ([]byte, Template52, error)

+ func (Template52) TemplateNumber() uint16

+ type Template5200 struct

+ BitsPerValue uint8

+ DecimalScaleFactor uint8

+ LevelValues []uint16

+ MaxLevelValue uint16

+ NumberOfLevelValues uint16

+ func (Template5200) TemplateNumber() uint16

+ type Template53 struct

+ NumberOfOctetsExtraDescriptors uint8

+ OrderOfSpatialDifferencing uint8

+ func PackComplexSpatialDiff(values []float64, bitsPerValue uint8, order uint8) ([]byte, Template53, error)

+ func (Template53) TemplateNumber() uint16

+ type Template54 struct

+ Precision uint8

+ func PackIEEE(values []float64, precision uint8) ([]byte, Template54, error)

+ func (Template54) TemplateNumber() uint16

+ type Template540 struct

+ TargetCompressionRatio uint8

+ TypeOfCompression uint8

+ func PackJPEG2000(values []float64, bitsPerValue uint8) ([]byte, Template540, error)

+ func (Template540) TemplateNumber() uint16

+ type Template542 struct

+ CcsdsBlockSize uint8

+ CcsdsFlags uint8

+ CcsdsRsi uint16

+ func PackCCSDS(values []float64, bitsPerValue uint8, blockSize uint8, rsi uint16) ([]byte, Template542, error)

+ func (Template542) TemplateNumber() uint16

+ type TimeRangeSpec struct

+ IndicatorOfUnitForTimeIncrement uint8

+ IndicatorOfUnitForTimeRange uint8

+ LengthOfTimeRange uint32

+ TimeIncrement uint32

+ TypeOfStatisticalProcessing uint8

+ TypeOfTimeIncrement uint8