# ECVT - convert float to string.

(Compatible with UNIX System V C)

### Usage:

char *ecvt();
str = ecvt(value,length,decimal,sign);

### Where:

- double value;
- is the floating point value to be converted.
- int length;
- is the number of digits that should be in the string
result.
- char *str;
- is a string of ASCII digits ending in the usual '\0'.
This string does NOT contain a sign or a decimal point.
For example, if "value" is -123.45,
"str" is the string "12345". The
first digit is non-zero (unless "value" is
zero). Trailing zeroes are added, if necessary, to pad
the number out to a length of "length". If
"length" is less than the number of digits
needed to represent "value", the result will be
rounded.
- int *decimal;
- points to storage for an integer. "ecvt" fills
this integer with the number of digits in "str"
that precede the decimal point. For example, if
"value" is 123.45, "ecvt" will assign
3 to "*decimal". This number can be negative if
the decimal point precedes the digits. For example, if
"value" is .00123, "ecvt" will assign
-2 to "*decimal".
- int *sign;
- points to storage for an integer. "ecvt" fills
this integer with zero if "value" is positive
or zero, and with a non-zero number if "value"
is negative.

### Description:

The "ecvt" function converts a floating point number
into a string of digits. The sign and the position of the decimal
point are indicated with values filled into "*sign" and
"*decimal" point, respectively.

Below, we give some examples. In all cases, "length"
is assumed to be 5.

value str *decimal *sign
----- --- -------- -----
1.23456 "12346" 1 zero
-344.10 "34410" 3 non-zero
0.12345 "12345" 0 zero
0.06890 "68900" -1 zero

### Notes:

This function comes from UNIX System V, where it was used as
part of the implementation of the "printf"
"%e" format specifier. On this system, however, it has
nothing to do with "%e", and therefore "ecvt"
and "printf" may differ on the way they convert some
floating point numbers into strings.

### See Also:

expl c lib fcvt

expl c lib sprintf

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