Struct ColumnReader 

pub struct ColumnReader<'a> { /* private fields */ }

A handle to one column of a BinTable, from BinTable::column_by_idx or BinTable::column_by_name. Decode through it without re-passing the column descriptor: raw for the typed values, physical for the scaled f64 plane, unsigned/complex/ bits for the special kinds, and vla (+ vla_physical/vla_bits) for variable-length P/Q columns. Borrows the table, so it cannot outlive it.

Implementations

impl<'a> ColumnReader<'a>

pub fn descriptor(&self) -> &'a Column

The column’s Column descriptor — name, TFORMn, TSCALn/TZEROn/TNULLn, TDIMn, TDISPn.

pub fn raw(&self) -> Result<ColumnData>

Decode a fixed-width column into a typed, row-flattened ColumnData: A is one String per row, every other fixed kind decodes from the concatenated cell bytes. Variable-length (P/Q) columns error here — use ColumnReader::vla.

pub fn physical(&self) -> Result<Vec<f64>>

The numeric column scaled to its physical f64 plane: TZEROn + TSCALn × raw, mapping integers equal to TNULLn to NaN. Errors for the non-numeric kinds (A/L/X/C/M) and variable-length columns.

pub fn unsigned(&self) -> Result<Option<UnsignedView>>

Exact typed integers when the column uses the FITS unsigned (or signed-byte) convention — TSCALn == 1, no TNULLn, TZEROn the matching sign-bit offset on a B/I/J/K column — without the f64 rounding of physical. Ok(None) for any other column; errors only for a variable-length column. Mirrors crate::Image::unsigned.

pub fn complex(&self) -> Result<Vec<Complex<f64>>>

A C/M complex column as Complex<f64> values, applying TZEROn + TSCALn × to each component (§6.4). Errors on non-complex columns.

pub fn bits(&self) -> Result<BitColumn<'a>>

An X (bit-array) column as a borrowed 2-D BitColumn — nrows × repeat bits viewed in place over the data unit, MSB-first (bit 0 is the MSB of the first byte, §7.3.2), with no per-row allocation. Errors on any non-X column.

pub fn vla(&self) -> Result<Vec<ColumnData>>

Decode a variable-length (P/Q) column: one ColumnData per row, each holding that row’s heap array (which may be empty). Errors for fixed-width columns.

pub fn vla_physical(&self) -> Result<Vec<Vec<f64>>>

Scale each row of a P/Q column to its physical plane: TZEROn + TSCALn × element, mapping integers equal to TNULLn to NaN (§6.4 — scaling applies to the heap values). Errors for fixed-width or non-numeric-heap columns.

pub fn vla_bits(&self) -> Result<BitColumn<'a>>

A variable-length X (1PX/1QX) column as a borrowed 2-D BitColumn, MSB-first (§7.3.2/§7.3.5 — the descriptor’s element count is the bit count). The rows are jagged (each its own length), so BitColumn::row(r).len() gives a row’s width. Errors on any non-bit VLA.

Trait Implementations

impl<'a> Clone for ColumnReader<'a>

fn clone(&self) -> ColumnReader<'a>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<'a> Debug for ColumnReader<'a>

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

Formats the value using the given formatter.

impl<'a> Copy for ColumnReader<'a>