Struct GRIB2Reader 

pub struct GRIB2Reader {
    pub packets: RefCell<Vec<Grib2Sections>>,
    pub idxs: Vec<Grib2SectionLocations>,
}

GRIB2 Reader

Description

This class reads a GRIB2 file and returns a list of GRIB2 products.

Implements the FeatureReader trait

Usage

The methods you have access to:

• GRIB2Reader::new: Create a new GRIB2Reader
• GRIB2Reader::from_idx: Create a GRIB2Reader with filtered .idx file data (see parse_idx and parsed_idx_from_url)
• GRIB2Reader::get_data: Get the Vector MultiPoint data
• GRIB2Reader::get_feature: Get the VectorFeature data

Associated methods that are useful:

• [fetch_gfs_data]: Fetch ATMOS or WAVE GFS data.
• parsed_idx_from_url: Given an input URL pointing to an IDX file, parse the sections
• parse_idx: Given an input string of an IDX file, parse the sections

The recommended way to parse grib files is to filter out what you want:

use gistools::{parsers::{BufferReader, FeatureReader}, readers::{parse_idx, GRIB2Reader}};
use std::{fs, path::PathBuf};

let mut path = PathBuf::from(env!("CARGO_MANIFEST_DIR"));
path.push("tests/readers/grib2/fixtures/ref_sec0.gdas.t12z.pgrb2.1p00.anl.75r.grib2.txt");

// parse the .idx file and apply a filter that we only need 3 sections
let idx_data = fs::read_to_string(path).unwrap();
let sections = parse_idx(
    idx_data,
    vec![":DZDT:0.01 mb:".into(), ":TMP:0.4 mb:".into(), ":ABSV:0.4 mb:anl:".into()],
    None,
);

// grab the grib2 file itself building with the filtered IDX sections
let mut path = PathBuf::from(env!("CARGO_MANIFEST_DIR"));
path.push("tests/readers/grib2/fixtures/ref_sec0.gdas.t12z.pgrb2.1p00.anl.75r.grib2");
let bytes = std::fs::read(path.clone()).unwrap();
let grib2_reader = GRIB2Reader::from_idx(&BufferReader::from(bytes), sections);

let features: Vec<_> = grib2_reader.iter().collect();
assert_eq!(features.len(), 1);

Parsing the entire grib file:

use gistools::{parsers::{BufferReader, FeatureReader}, readers::GRIB2Reader};
use std::{fs, path::PathBuf};

let mut path = PathBuf::from(env!("CARGO_MANIFEST_DIR"));
path.push("tests/readers/grib2/fixtures/ref_simple_packing.grib2");

let bytes = fs::read(path.clone()).unwrap();
let grib2_reader = GRIB2Reader::new(BufferReader::from(bytes).into(), vec![]);

let features: Vec<_> = grib2_reader.iter().collect();
assert_eq!(features.len(), 1);

Links

• https://en.wikipedia.org/wiki/GRIB
• https://www.nco.ncep.noaa.gov/pmb/docs/grib2/grib2_doc/

Fields

packets: RefCell<Vec<Grib2Sections>>

The GRIB2 packets

idxs: Vec<Grib2SectionLocations>

The list of section locations

Implementations

impl GRIB2Reader

pub fn new<T: Reader>( readers: GRIB2ReaderInput<T>, idxs: Vec<Grib2SectionLocations>, ) -> Self

Create a GRIB2Reader

Parameters

• readers: Reader(s) for entire GRIB file. If array, its grib chunks, otherwise it will be the entire file
• idxs: The list of section locations we will be parsing

Returns

A GRIB2Reader

pub fn from_idx<T: Reader>( source: &T, idxs: Vec<Grib2SectionLocations>, ) -> GRIB2Reader

Create a GRIB2Reader from a .idx file

Parameters

• source: Either the http path to the .idx file or the entire GRIB file
• idxs: The parsed .idx file with the locations of each section

Returns

A GRIB2Reader of the specific sections

pub fn get_data(&self) -> Option<VectorMultiPoint>

Get the Vector Point feature data

pub fn get_feature(&self) -> Option<GRIB2VectorFeature>

Get the Vector Point feature

Trait Implementations

impl Clone for GRIB2Reader

fn clone(&self) -> GRIB2Reader

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for GRIB2Reader

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl FeatureReader<Vec<Grib2ProductDefinition>, Map<String, ValueType>, Map<String, ValueType>> for GRIB2Reader

A feature reader trait with a callback-based approach

type FeatureIterator<'a> = GRIB2Iterator<'a>

The Feature Reader should implement an iterator of some kind

fn iter(&self) -> Self::FeatureIterator<'_>

All readers have an iter function that returns a Iterator struct

fn par_iter( &self, _pool_size: usize, thread_id: usize, ) -> Self::FeatureIterator<'_>

All readers have a par_iter function that returns a ParallelIterator struct