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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 con-trolled controlled
                                        trolled 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 interpreters.

       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  signifi- |
       cance.   If  the value is zero (the default), the result will have the fewest digits needed to repre- |
       sent 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.


KEYWORDS
       conversion, double-precision, floating-point, string



Tcl                                                  8.0                                  Tcl_PrintDouble(3)