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TAscColumn

Unit DeLaFitsAscTable

Type type

PAscColumn = ^TAscColumn;
TAscColumn = record
  Position: Integer;
  Form: string;
  Name: string;
  Umit: string;
  Scal: Extended;
  Zero: Extended;
  Null: string;
  Disp: string;
  Dmin: Extended;
  Dmax: Extended;
  Lmin: Extended;
  Lmax: Extended;
end;

Description

The ASCII-table extension provides a means of storing catalogs and tables of astronomical data in FITS format. Each row of the table consists of a fixed-length sequence of ASCII characters divided into fields that correspond to the columns in the table The FITS Standard, Sect. 7.2

Table column parameters from ASCII-TABLE extension

  • Position ~ TBCOLn keyword - integer specifying the position in which column starts (the first position of a row is numbered 1)
  • Form ~ TFORMn keywords - character string describing the format in which column is encoded
  • Name ~ TTYPEn keywords - character string giving the name of column
  • Umit ~ TUNITn keywords - character string describing the physical units in which the quantity in column
  • Scal ~ TSCALn keywords - shall be used, along with the TZEROn keyword, to linearly scale the values in the column to transform them into the physical values
  • Zero ~ TZEROn keywords - shall be used, along with the TSCALn keyword, to linearly scale the values in the column to transform them into the physical values
  • Null ~ TNULLn keywords - character string that represents an undefined value for column
  • Disp ~ TDISPn keywords - character string describing the format recommended for displaying an ASCII-text representation of the contents of column
  • Dmin ~ TDMINn keywords - number giving the minimum physical value contained in column
  • Dmax ~ TDMAXn keywords - number giving the maximum physical value contained in column
  • Lmin ~ TLMINn keywords - number that specifies the minimum physical value in column that has a valid meaning or interpretation
  • Lmax ~ TLMAXn keywords - number that specifies the maximum physical value in column that has a valid meaning or interpretation

It is recommended to instantiate columns using the AscColumnCreateString and AscColumnCreateNumber functions