---
name: "PrintDbl"
section: "3tcl"
platform: "linux"
package: "tcl8.3-doc"
version: "8.3.5-13"
release: "Debian 5.0 (Lenny)"
platforms: ["linux"]
url: "https://new.carta.tech/PrintDbl/3tcl"
---

# PrintDbl(3tcl)

Convert floating value to string

```

```

## 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 interpreters.

- double *value* (in)

  Floating-point value to be converted.

- char *\*dst* (out)

  Where to store string representing *value*.  Must have at least TCL\_DOUBLE\_SPACE characters of storage.

  ```

  ```

## 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 doesn't look like an integer.  Where **%g** would generate an integer with no decimal point, **Tcl\_PrintDouble** adds \`\`.0''.

## KEYWORDS

conversion, double-precision, floating-point, string