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- 1
- Write elements into an ASCII or binary table column (in the CDU).
The datatype of the array is implied by the suffix of the
routine name.
int fits_write_col_str / ffpcls
(fitsfile *fptr, int colnum, long firstrow, long firstelem,
long nelements, char **array, > int *status)
int fits_write_col_[log,byt,sht,usht,int,uint,lng,ulng,lnglng,flt,dbl,cmp,dblcmp] /
ffpcl[l,b,i,ui,k,uk,j,uj,jj,e,d,c,m]
(fitsfile *fptr, int colnum, long firstrow,
long firstelem, long nelements, DTYPE *array, > int *status)
- 2
- Write elements into an ASCII or binary table column
substituting the appropriate FITS null value for any elements that
are equal to the nulval parameter. This routines must not be used to
write to variable length array columns.
int fits_write_colnull_[log, byt, sht, usht, int, uint, lng, ulng, lnglng, flt, dbl] /
ffpcn[l,b,i,ui,k,uk,j,uj,jj,e,d]
(fitsfile *fptr, int colnum, long firstrow, long firstelem,
long nelements, DTYPE *array, DTYPE nulval, > int *status)
- 3
- Write string elements into a binary table column (in the CDU)
substituting the FITS null value for any elements that
are equal to the nulstr string. This routine must NOT be
used to write to variable length array columns.
int fits_write_colnull_str / ffpcns
(fitsfile *fptr, int colnum, long firstrow, long firstelem,
long nelements, char **array, char *nulstr, > int *status)
- 4
- Write bit values into a binary byte ('B') or bit ('X') table column (in
the CDU). Larray is an array of characters corresponding to the
sequence of bits to be written. If an element of larray is true
(not equal to zero) then the corresponding bit in the FITS table is
set to 1, otherwise the bit is set to 0. The 'X' column in a FITS
table is always padded out to a multiple of 8 bits where the bit
array starts with the most significant bit of the byte and works
down towards the 1's bit. For example, a '4X' array, with the
first bit = 1 and the remaining 3 bits = 0 is equivalent to the 8-bit
unsigned byte decimal value of 128 ('1000 0000B'). In the case of
'X' columns, CFITSIO can write to all 8 bits of each byte whether
they are formally valid or not. Thus if the column is defined as
'4X', and one calls ffpclx with firstbit=1 and nbits=8, then all
8 bits will be written into the first byte (as opposed to writing
the first 4 bits into the first row and then the next 4 bits into
the next row), even though the last 4 bits of each byte are formally
not defined and should all be set = 0. It should also be noted that
it is more efficient to write 'X' columns an entire byte at a time,
instead of bit by bit. Any of the CFITSIO routines that write to
columns (e.g. fits_write_col_byt) may be used for this purpose.
These routines will interpret 'X' columns as though they were 'B'
columns (e.g., '1X' through '8X' is equivalent
to '1B', and '9X' through '16X' is equivalent to '2B').
int fits_write_col_bit / ffpclx
(fitsfile *fptr, int colnum, long firstrow, long firstbit,
long nbits, char *larray, > int *status)
- 5
- Write the descriptor for a variable length column in a binary table.
This routine can be used in conjunction with ffgdes to enable
2 or more arrays to point to the same storage location to save
storage space if the arrays are identical.
int fits_write_descript / ffpdes
(fitsfile *fptr, int colnum, long rownum, long repeat,
long offset, > int *status)
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