Tcl_PrintDouble(3) Tcl Library Procedures Tcl_PrintDouble(3)______________________________________________________________________________NAMETcl_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 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_DOU‐
BLE_SPACE characters of storage.
_________________________________________________________________DESCRIPTIONTcl_PrintDouble generates a string that represents the value of value
and stores it in memory at the location given by dst. It uses %g for‐
mat to generate the string, with one special twist: the string is guar‐
anteed 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.
KEYWORDS
conversion, double-precision, floating-point, string
Tcl 8.0 Tcl_PrintDouble(3)
