Struct FitsHeader

Source

pub struct FitsHeader {
    pub cards: Vec<FitsHeaderCard>,
}

Available on crate feature fits only.

Expand description

The header portion of an HDU.

Fields§

§cards: Vec<FitsHeaderCard>

The card images contained in the header.

Implementations§

Source §

impl FitsHeader

Source

pub fn new() -> Self

Constructs an empty header.

Source

pub fn from_bytes(raw: Vec<u8>) -> FitsHeader

Constructs a FitsHeader from the given bytes.

§Examples

use astro_rs::fits::*;
use std::rc::Rc;

// default primary HDU header bytes
let bytes = *b"SIMPLE  =                    T                                                  BITPIX  =                    8                                                  NAXIS   =                    0                                                  END                                                                             ";
let mut header = FitsHeader::from_bytes(bytes.to_vec());

assert!(*header
    .get_card(SIMPLE_KEYWORD)
    .and_then(|card| card.get_value::<bool>().ok())
    .unwrap_or_default());
assert_eq!(
    header
        .get_card(BITPIX_KEYWORD)
        .and_then(|card| card.get_value::<Bitpix>().ok()),
    Some(Rc::new(Bitpix::U8))
);
assert_eq!(
    header
        .get_card(NAXIS_KEYWORD)
        .and_then(|card| card.get_value::<u16>().ok()),
    Some(Rc::new(0))
);
assert!(header.get_card(END_KEYWORD).is_some());

Source

pub fn to_bytes(self) -> Vec<u8> ⓘ

Serializes the header into bytes.

§Examples

use astro_rs::fits::*;

let hdu = primary_hdu::default();
let mut bytes = b"SIMPLE  =                    T                                                  BITPIX  =                    8                                                  NAXIS   =                    0                                                  END                                                                             ".to_vec();
bytes.resize(2880, b' ');

assert_eq!(hdu.header.to_bytes(), bytes);

Source

pub fn get_card<K: PartialEq<FitsHeaderKeyword>>( &mut self, keyword: K, ) -> Option<&mut FitsHeaderCard>

Searches the header cards for a match with the given keyword.

§Examples

use astro_rs::fits::*;

let mut hdu = primary_hdu::default();
assert!(hdu.header.get_card(SIMPLE_KEYWORD).is_some());
assert!(hdu.header.get_card(EXTNAME_KEYWORD).is_none());

Source

pub fn set_card<K: PartialEq<FitsHeaderKeyword> + Into<FitsHeaderKeyword>, T: FitsHeaderValue + 'static>( &mut self, keyword: K, value: T, comment: Option<String>, ) -> Result<(), FitsHeaderError>

Sets the value and comment of the card with the given keyword. If a card already exists, the data is overwritten. If a card does not exist, one is created.

§Examples

use astro_rs::fits::*;
use std::rc::Rc;

let mut header = FitsHeader::new();
header.set_card(SIMPLE_KEYWORD, true, None);
assert!(*header
    .get_card(SIMPLE_KEYWORD)
    .and_then(|card| card.get_value::<bool>().ok())
    .unwrap_or_default());

header.set_card(SIMPLE_KEYWORD, false, Some(String::from("FITS STANDARD")));
let mut card = header.get_card(SIMPLE_KEYWORD).unwrap();
assert!(!*card.get_value::<bool>()?);
assert_eq!(card.get_comment()?, Rc::new(String::from("FITS STANDARD")));

Source

pub fn set_value<K, T: FitsHeaderValue + 'static>( &mut self, keyword: K, value: T, ) -> Result<(), FitsHeaderError>
where K: PartialEq<FitsHeaderKeyword> + Into<FitsHeaderKeyword>,

Sets the value of the card with the given keyword. If a card already exists, the value is overwritten, and the comment is retained. If a card does not exist, one is created.

§Examples

use astro_rs::fits::*;
use std::rc::Rc;

let bytes = *b"SIMPLE  =                    T / FITS STANDARD                                  ";
let mut header = FitsHeader::from_bytes(bytes.to_vec());
header.set_value(SIMPLE_KEYWORD, false)?;
let mut card = header.get_card(SIMPLE_KEYWORD).unwrap();
assert!(!*card.get_value::<bool>()?);
assert_eq!(card.get_comment()?, Rc::new(String::from("FITS STANDARD")));

header.set_value(BITPIX_KEYWORD, Bitpix::U8)?;
assert_eq!(
    header
        .get_card(BITPIX_KEYWORD)
        .and_then(|card| card.get_value::<Bitpix>().ok()),
    Some(Rc::new(Bitpix::U8))
);

Source

pub fn set_comment<K: PartialEq<FitsHeaderKeyword>>( &mut self, keyword: K, comment: Option<String>, ) -> Result<(), FitsHeaderError>

Sets the comment of the card with the given keyword. If a card already exists, the comment is overwritten, and the value is retained. If a card does not exist, this function has no effect.

§Examples

use astro_rs::fits::*;
use std::rc::Rc;

let mut hdu = primary_hdu::default();
hdu.header.set_comment(SIMPLE_KEYWORD, Some(String::from("FITS STANDARD")));
let mut card = hdu.header.get_card(SIMPLE_KEYWORD).unwrap();
assert!(*card.get_value::<bool>()?);
assert_eq!(card.get_comment()?, Rc::new(String::from("FITS STANDARD")));

hdu.header.set_comment(EXTNAME_KEYWORD, Some(String::from("Error 404")));
assert!(hdu.header.get_card(EXTNAME_KEYWORD).is_none());