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'\"
'\" Copyright (c) 1989-1993 The Regents of the University of California.
'\" Copyright (c) 1994-1997 Sun Microsystems, Inc.
'\"
'\" See the file "license.terms" for information on usage and redistribution
'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
'\"
.TH Tcl_PrintDouble 3 8.0 Tcl "Tcl Library Procedures"
.so man.macros
.BS
.SH NAME
Tcl_PrintDouble \- Convert floating value to string
.SH SYNOPSIS
.nf
\fB#include <tcl.h>\fR
.sp
\fBTcl_PrintDouble\fR(\fIinterp, value, dst\fR)
.fi
.SH ARGUMENTS
.AS Tcl_Interp *interp out
.AP Tcl_Interp *interp in
This argument is ignored.
.AP double value in
Floating-point value to be converted.
.AP char *dst out
Where to store the string representing \fIvalue\fR. Must have at
least \fBTCL_DOUBLE_SPACE\fR characters of storage.
.BE
.SH DESCRIPTION
.PP
\fBTcl_PrintDouble\fR generates a string that represents the value
of \fIvalue\fR and stores it in memory at the location given by
\fIdst\fR. It uses \fB%g\fR format to generate the string, with one
special twist: the string is guaranteed to contain either a
.QW .
or an
.QW e
so that it does not look like an integer. Where \fB%g\fR would
generate an integer with no decimal point, \fBTcl_PrintDouble\fR adds
.QW .0 .
.PP
The result will have the fewest digits needed to
represent the number in such a way that \fBTcl_NewDoubleObj\fR
will generate the same number when presented with the given string.
IEEE semantics of rounding to even apply to the conversion.
.SH KEYWORDS
conversion, double-precision, floating-point, string
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