- 1
- Get the byte offsets in the FITS file to the start of the header
and the start and end of the data in the CHDU. The difference
between headstart and dataend equals the size of the CHDU. If the
CHDU is the last HDU in the file, then dataend is also equal to the
size of the entire FITS file. Null pointers may be input for any
of the address parameters if their values are not needed.
int fits_get_hduaddr / ffghad (only supports files up to 2.1 GB in size)
(fitsfile *fptr, > long *headstart, long *datastart, long *dataend,
int *status)
int fits_get_hduaddrll / ffghadll (supports large files)
(fitsfile *fptr, > LONGLONG *headstart, LONGLONG *datastart,
LONGLONG *dataend, int *status)
- 2
- Create (append) a new empty HDU at the end of the FITS file.
This is now the CHDU but it is completely empty and has
no header keywords. It is recommended that fits_create_img or
fits_create_tbl be used instead of this routine.
int fits_create_hdu / ffcrhd
(fitsfile *fptr, > int *status)
- 3
- Insert a new IMAGE extension immediately following the CHDU, or
insert a new Primary Array at the beginning of the file. Any
following extensions in the file will be shifted down to make room
for the new extension. If the CHDU is the last HDU in the file
then the new image extension will simply be appended to the end of
the file. One can force a new primary array to be inserted at the
beginning of the FITS file by setting status = PREPEND_PRIMARY prior
to calling the routine. In this case the old primary array will be
converted to an IMAGE extension. The new extension (or primary
array) will become the CHDU. Refer to Chapter 9 for a list of
pre-defined bitpix values.
int fits_insert_img / ffiimg
(fitsfile *fptr, int bitpix, int naxis, long *naxes, > int *status)
int fits_insert_imgll / ffiimgll
(fitsfile *fptr, int bitpix, int naxis, LONGLONG *naxes, > int *status)
- 4
- Insert a new ASCII or binary table extension immediately following the CHDU.
Any following extensions will be shifted down to make room for the
new extension. If there are no other following extensions then the
new table extension will simply be appended to the end of the
file. If the FITS file is currently empty then this routine will
create a dummy primary array before appending the table to it. The
new extension will become the CHDU. The tunit and extname
parameters are optional and a null pointer may be given if they are
not defined. When inserting an ASCII table with
fits_insert_atbl, a null pointer may given for the *tbcol
parameter in which case each column of the table will be separated
by a single space character. Similarly, if the input value of
rowlen is 0, then CFITSIO will calculate the default rowlength
based on the tbcol and ttype values. Under normal circumstances,
the nrows
paramenter should have a value of 0; CFITSIO will automatically update
the number of rows as data is written to the table. When inserting a binary table
with fits_insert_btbl, if there are following extensions in the
file and if the table contains variable length array columns then
pcount must specify the expected final size of the data heap,
otherwise pcount must = 0.
int fits_insert_atbl / ffitab
(fitsfile *fptr, LONGLONG rowlen, LONGLONG nrows, int tfields, char *ttype[],
long *tbcol, char *tform[], char *tunit[], char *extname, > int *status)
int fits_insert_btbl / ffibin
(fitsfile *fptr, LONGLONG nrows, int tfields, char **ttype,
char **tform, char **tunit, char *extname, long pcount, > int *status)
- 5
- Modify the size, dimensions, and/or data type of the current
primary array or image extension. If the new image, as specified
by the input arguments, is larger than the current existing image
in the FITS file then zero fill data will be inserted at the end
of the current image and any following extensions will be moved
further back in the file. Similarly, if the new image is
smaller than the current image then any following extensions
will be shifted up towards the beginning of the FITS file
and the image data will be truncated to the new size.
This routine rewrites the BITPIX, NAXIS, and NAXISn keywords
with the appropriate values for the new image.
int fits_resize_img / ffrsim
(fitsfile *fptr, int bitpix, int naxis, long *naxes, > int *status)
int fits_resize_imgll / ffrsimll
(fitsfile *fptr, int bitpix, int naxis, LONGLONG *naxes, > int *status)
- 6
- Copy the data (and not the header) from the CHDU associated with infptr
to the CHDU associated with outfptr. This will overwrite any data
previously in the output CHDU. This low level routine is used by
fits_copy_hdu, but it may also be useful in certain application programs
that want to copy the data from one FITS file to another but also
want to modify the header keywords. The required FITS header keywords
which define the structure of the HDU must be written to the
output CHDU before calling this routine.
int fits_copy_data / ffcpdt
(fitsfile *infptr, fitsfile *outfptr, > int *status)
- 7
- Read or write a specified number of bytes starting at the specified byte
offset from the start of the extension data unit. These low
level routine are intended mainly for accessing the data in
non-standard, conforming extensions, and should not be used for standard
IMAGE, TABLE, or BINTABLE extensions.
int fits_read_ext / ffgextn
(fitsfile *fptr, LONGLONG offset, LONGLONG nbytes, void *buffer)
int fits_write_ext / ffpextn
(fitsfile *fptr, LONGLONG offset, LONGLONG nbytes, void *buffer)
- 8
- This routine forces CFITSIO to rescan the current header keywords that
define the structure of the HDU (such as the NAXIS and BITPIX
keywords) so that it reinitializes the internal buffers that
describe the HDU structure. This routine is useful for
reinitializing the structure of an HDU if any of the required
keywords (e.g., NAXISn) have been modified. In practice it should
rarely be necessary to call this routine because CFITSIO
internally calls it in most situations.
int fits_set_hdustruc / ffrdef
(fitsfile *fptr, > int *status) (DEPRECATED)
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