Tcl_PrintDouble(3)

Tcl_PrintDouble(3)   Tcl Library Procedures    Tcl_PrintDouble(3)

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NAME

     Tcl_PrintDouble - Convert floating value to string

SYNOPSIS

     #include <tcl.h>

     Tcl_PrintDouble(interp, value, dst)

ARGUMENTS

     Tcl_Interp *interp (in)          Before   Tcl    8.0,    the
                                      tcl_precision  variable  in
                                      this interpreter controlled
                                      the  conversion.  As of Tcl
                                      8.0,   this   argument   is
                                      ignored  and the conversion
                                      is   controlled   by    the
                                      tcl_precision variable that
                                      is now shared by all inter-
                                      preters.

     double value (in)                Floating-point value to  be
                                      converted.

     char *dst (out)                  Where to store  the  string
                                      representing  value.   Must
                                      have        at        least
                                      TCL_DOUBLE_SPACE characters
                                      of storage.
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DESCRIPTION

     Tcl_PrintDouble generates a string that represents the value
     of  value  and  stores it in memory at the location given by
     dst.  It uses %g format to generate  the  string,  with  one
     special  twist: the string is guaranteed to contain either a
     "." or an "e" so that it does  not  look  like  an  integer.
     Where  %g  would  generate an integer with no decimal point,
     Tcl_PrintDouble adds ".0".                                    |

     If the tcl_precision value is non-zero, the result will have  |
     precisely that many digits of significance.  If the value is  |
     zero (the default), the result will have the  fewest  digits  |
     needed   to   represent  the  number  in  such  a  way  that  |
     Tcl_NewDoubleObj  will  generate  the   same   number   when  |
     presented with the given string.  IEEE semantics of rounding  |
     to even apply to the conversion.

Tcl                     Last change: 8.0                        1

Tcl_PrintDouble(3)   Tcl Library Procedures    Tcl_PrintDouble(3)

KEYWORDS

     conversion, double-precision, floating-point, string

Tcl                     Last change: 8.0                        2