matlab.io.fits.createTbl

Create new ASCII or binary table extension

Syntax

fptr = createTbl(fptr,tbltype,nrows,ttype,tform,tunit,extname)


Description

fptr = createTbl(fptr,tbltype,nrows,ttype,tform,tunit,extname) creates a new ASCII or bintable table extension. tbltype must be either 'binary' or 'ascii'. The nrows argument gives the initial number of rows to be created in the table and should normally be zero. tunit specifies the units for each column, but can be an empty cell array if no units are desired. extname specifies the extension name, but can be omitted.

tform contains the format of the column, specified as a cell array of character vectors or a string array. For binary tables, the values should be in the form of 'rt', where 'r' is the repeat count and 't' is one of the following letters.

'A'	ASCII character
'B'	Byte or uint8
'C'	Complex (single precision)
'D'	Double precision
'E'	Single precision
'I'	int16
'J'	int32
'K'	int64
'L'	Logical
'M'	Complex (double precision)
'X'	Bit (int8 zeros and ones)

A column can also be specified as having variable-width if the tform value has the form '1Pt' or '1Qt', where 't' specifies the data type as above.

For ASCII tables, tform contains values that take the form:

'Iw'	int16 column with width 'w'
'Aw'	ASCII column with width 'w'
'Fww.dd'	Fixed point
'Eww.dd'	Single precision with width 'ww' and precision 'dd'
'Dww.dd'	Double precision with width 'ww' and precision 'dd'

This function corresponds to the fits_create_tbl(ffcrtb) function in the CFITSIO library C API.

Examples

Create a binary table. The first column contains strings of nine characters each. The second column contains four-element sequences of bits. The third column contains three-element sequences of uint8 values. The fourth column contains double-precision scalars.

import matlab.io.*
fptr = fits.createFile('myfile.fits');
ttype = {'Col1','Col2','Col3','Col4'};
tform = {'9A','4X','3B','1D'};
tunit = {'m/s','kg','kg/m^3','candela'};
fits.createTbl(fptr,'binary',10,ttype,tform,tunit,'my-table');
fits.closeFile(fptr);
fitsdisp('myfile.fits');

Create a two-column table where the first column has a single double-precision value, but the second column has a variable-length double-precision value.

import matlab.io.*
fptr = fits.createFile('myfile2.fits');
ttype = {'Col1','Col2'};
tform = {'1D','1PD'};
fits.createTbl(fptr,'binary',0,ttype,tform);
fits.closeFile(fptr);
fitsdisp('myfile2.fits');