Provided by: libgetdata-dev_0.7.3-6_i386 bug

NAME

       gd_alter_bit,    gd_alter_carray,   gd_alter_clincom,   gd_alter_const,
       gd_alter_cpolynom, gd_alter_crecip,  gd_alter_divide,  gd_alter_lincom,
       gd_alter_linterp,  gd_alter_multiply, gd_alter_phase, gd_alter_polynom,
       gd_alter_raw, gd_alter_recip, gd_alter_sbit --  modify  a  field  in  a
       dirfile

SYNOPSIS

       #include <getdata.h>

       int gd_alter_bit(DIRFILE *dirfile, const char *field_code, const char
              *in_field, gd_bit_t bitnum, gd_bit_t numbits);

       int gd_alter_carray(DIRFILE *dirfile, const char *field_code, gd_type_t
              const_type, size_t array_len);

       int gd_alter_clincom(DIRFILE *dirfile, const char *field_code, int
              n_fields, const char **in_fields, const double complex *cm,
              const double complex *cb);

       int gd_alter_const(DIRFILE *dirfile, const char *field_code, gd_type_t
              const_type);

       int gd_alter_cpolynom(DIRFILE *dirfile, const char *field_code, int
              poly_ord, const char *in_field, const double complex *ca);

       int gd_alter_crecip(DIRFILE *dirfile, const char *field_code, const
              char *in_field, complex double cdividend);

       int gd_alter_divide(DIRFILE *dirfile, const char *field_code, const
              char *in_field1, const char *in_field2);

       int gd_alter_lincom(DIRFILE *dirfile, const char *field_code, int
              n_fields, const char **in_fields, const double *m, const double
              *b);

       int gd_alter_linterp(DIRFILE *dirfile, const char *field_code, const
              char *in_field, const char *table, int rename_table);

       int gd_alter_multiply(DIRFILE *dirfile, const char *field_code, const
              char *in_field1, const char *in_field2);

       int gd_alter_phase(DIRFILE *dirfile, const char *field_code, const char
              *in_field, gd_shift_t shift);

       int gd_alter_polynom(DIRFILE *dirfile, const char *field_code, int
              poly_ord, const char *in_field, const double *ca);

       int gd_alter_raw(DIRFILE *dirfile, const char *field_code, gd_type_t
              data_type, gd_spf_t spf, int recode);

       int gd_alter_recip(DIRFILE *dirfile, const char *field_code, const char
              *in_field, double dividend);

       int gd_alter_sbit(DIRFILE *dirfile, const char *field_code, const char
              *in_field, gd_bit_t bitnum, gd_bit_t numbits);

DESCRIPTION

       These functions provide alternatives  to  using  the  gd_alter_entry(3)
       function  to  modify  a  field  of  the  indicated  type in the dirfile
       specified by dirfile.

       In all of these  calls,  field_code  indicates  the  the  field  to  be
       modified, which may be a regular field, or a metafield specified by its
       full (slashed) field code, but  should  not  contain  a  representation
       suffix.  The meaning and valid types of other arguments may be obtained
       from the get_entry(3) and dirfile-format(5) manual pages.  The gd_bit_t
       type  is a signed 16-bit integer type.  The gd_shift_t type is a signed
       64-bit integer type.  The gd_spf_t type is an unsigned  16-bit  integer
       type.

       The  gd_alter_clincom() and gd_alter_cpolynom() functions are identical
       to gd_alter_lincom() and gd_alter_polynom(), except they  take  complex
       scalar  parameters,  instead  of purely real values.  This only matters
       for the input of new parameters;  if  the  scalar  parameters  are  not
       changed  (by  passing NULL instead of a list of scalars), the functions
       can be used interchangeably, regardless of whether  the  altered  field
       has complex scalar parameters or not.

       If    the   corresponding   parameters   are   to   be   changed,   the
       gd_alter_lincom() and gd_alter_clincom()  functions  take  pointers  to
       three  arrays  of  length  n_fields  containing  the  input field names
       (in_fields), the gain factors (m or cm), and the  offset  terms  (b  or
       cb).   Similarly,  gd_alter_polynom()  and  gd_alter_cpolynom() take an
       array of length poly_ord + 1 containing the polynomial co-efficients (a
       or ca).

       Some  field  parameters  have  special  values which indicate no change
       should be made to the parameter.  Specifically, if any  of  the  string
       parameters  or m, b, or a (cm, cb, or ca) are NULL, the old values will
       be retained.  Similarly,  if  spf,  n_fields,  numbits,  cdividend,  or
       dividend  is  zero,  or if bitnum is -1, or if data_type, or const_type
       are equal to GD_NULL, these parameters will not be modified.

       All field  parameters  introduced  with  this  interface  must  contain
       literal parameters.  Field parameters which are scalar fields cannot be
       introduced with these functions.  To do  that,  use  gd_alter_entry(3),
       gd_alter_spec(3) or gd_malter_spec(3), as appropriate.

       If  rename_table  is  non-zero,  the  look-up  table  referenced by the
       LINTERP field will be renamed to the path given by table.  If recode is
       non-zero,  the  binary  file  associated with the RAW field will be re-
       encoded to reflect the new field parameters.

       See      NOTES      below      for      information      on       using
       gd_alter_clincom(),  gd_alter_crecip(),  and gd_alter_cpolynom() in the
       C89 GetData API.

RETURN VALUE

       On success, any of these functions returns  zero.    On  error,  -1  is
       returned  and  the  dirfile  error  is  set  to a non-zero error value.
       Possible error values are:

       GD_E_ACCMODE
               The specified dirfile was opened read-only.

       GD_E_ALLOC
               The library was unable to allocate memory.

       GD_E_BAD_CODE
               The field specified by field_code was not found.

       GD_E_BAD_DIRFILE
               The supplied dirfile was invalid.

       GD_E_BAD_ENTRY
               One or more of the field parameters specified was invalid.

       GD_E_BAD_FIELD_TYPE
               The field specified by field_code was of the wrong type for the
               function called.

       GD_E_BAD_TYPE
               The data_type or const_type argument was invalid.

       GD_E_PROTECTED
               The  metadata of the fragment was protected from change.  Or, a
               request to translate the binary  file  associated  with  a  RAW
               field   was  attempted,  but  the  data  of  the  fragment  was
               protected.

       GD_E_RAW_IO
               An  I/O  error  occurred  while  translating  the  binary  file
               associated  with a modified RAW field, or an I/O error occurred
               while attempting to rename a LINTERP table file.

       GD_E_UNKNOWN_ENCODING
               The encoding  scheme  of  the  indicated  format  specification
               fragment is not known to the library.  As a result, the library
               was unable to translate the binary file be  associated  with  a
               modified RAW field.

       GD_E_UNSUPPORTED
               The  encoding  scheme  of  the  indicated  format specification
               fragment  does  not  support  translating   the   binary   file
               associated with a modified RAW field.

       The   dirfile  error  may  be  retrieved  by  calling  gd_error(3).   A
       descriptive error string for the last error encountered can be obtained
       from a call to gd_error_string(3).

NOTES

       The    C89    GetData    API    provides   different   prototypes   for
       gd_alter_clincom(), gd_alter_cpolynom(), and gd_alter_crecip():

       #define GD_C89_API
       #include <getdata.h>

       int gd_alter_clincom(DIRFILE *dirfile, const char *field_code,
              int n_fields, const char **in_fields, const double *cm,
              const double *cb);

       int gd_alter_cpolynom(DIRFILE *dirfile, const char *field_code,
              int poly_ord, const char *in_fields, const double *ca);

       int gd_alter_crecip(DIRFILE *dirfile, const char *field_code,
              const char *in_field, double cdividend[2]);

       In this case, the array pointers passed as cm, cb  or  ca  should  have
       twice  as  many  (purely real) elements, consisting of alternating real
       and imaginary parts for the complex data.  For example, ca[0] should be
       the  real  part  of the first co-efficient, ca[1] the imaginary part of
       the first co-efficient, ca[2] the real part of the second co-efficient,
       ca[3]  the  imaginary  part  of  the  second  co-efficient,  and so on.
       Similarly, the cdividend parameter becomes a double precision array  of
       length two.

SEE ALSO

       gd_alter_entry(3),  gd_alter_spec(3),  gd_error(3), gd_error_string(3),
       gd_malter_spec(3), gd_metaflush(3), gd_open(3), dirfile-format(5)