SFF++ library: reading and writing SFF from C++
Public Member Functions | Public Attributes | Static Public Attributes | List of all members
sff::DAST Struct Reference

#include <sffxx.h>

Public Member Functions

 DAST ()
 
 DAST (std::istream &is)
 
std::string line () const
 
void read (std::istream &is, const bool &debug=false)
 

Public Attributes

int nchar
 
double ampfac
 
bool hasfree
 
bool hasinfo
 
bool last
 

Static Public Attributes

static const char *const LINEID ="DAST"
 

Detailed Description

Data status line providing scaling factors and required buffer size.

definition of DAST line: 

c     position   format   contents
c     1-5        a5       DAST  (identifier)
c     7-16       i10      number of characters in encoded dataset
c                         From library version 1.10 this field may be -1.
c                         In this case the reading program has to determine
c                         the number of characters itself by detecting the
c                         CHK2 line. This change was necessary to implement
c                         the C++ version of libsff since this starts writing
c                         without having encoded the whole trace already.
c     18-33      e16.6    ampfac
c                         This is a factor to scale the (floating point)
c                         dataset to an desireable dynamic range
c                         before converting it to Fortran integer
c                         values. After reading the dataset and
c                         decoding and converting it to floating point
c                         you have to multiply each sample by ampfac
c                         to get back the original values.
c                         As the maximum range of integer values goes
c                         from -(2.**31) to (2.**31)-1 you might
c                         like to adjust the maximum integer value
c                         to 0x7FFFFFFF. This may cause problems
c                         as the second differences compressing algorithm
c                         may increase the dynamic range of your data
c                         by a factor of four in the worst case.
c                         It is save to adjust the largest absolute
c                         value in the dataset to (2.**23)-1 which
c                         is 0x7FFFFF.
c                         The underlying libgsexx limits the maximum value to
c                         2**27-1. We adopt this here (thof, 21.11.2011)
c     35-44      a10      code with a combination of three possible
c                         characters indicating possible optional blocks
c                         and a following further dataset:
c                           F    a FREE block follows after dataset
c                           I    an INFO line follows after dataset
c                           D    there is another Data Block following
c                                in this file (this must be the last
c                                character in code)

 \sa \ref subsec_definition_dast_line

Definition at line 179 of file sffxx.h.

The documentation for this struct was generated from the following files: