| 0,0 → 1,208 |
|---|
| /* |
| FUNCTION |
| <<ecvt>>, <<ecvtf>>, <<fcvt>>, <<fcvtf>>---double or float to string |
| |
| INDEX |
| ecvt |
| INDEX |
| ecvtf |
| INDEX |
| fcvt |
| INDEX |
| fcvtf |
| |
| ANSI_SYNOPSIS |
| #include <stdlib.h> |
| |
| char *ecvt(double <[val]>, int <[chars]>, int *<[decpt]>, int *<[sgn]>); |
| char *ecvtf(float <[val]>, int <[chars]>, int *<[decpt]>, int *<[sgn]>); |
| |
| char *fcvt(double <[val]>, int <[decimals]>, |
| int *<[decpt]>, int *<[sgn]>); |
| char *fcvtf(float <[val]>, int <[decimals]>, |
| int *<[decpt]>, int *<[sgn]>); |
| |
| TRAD_SYNOPSIS |
| #include <stdlib.h> |
| |
| char *ecvt(<[val]>, <[chars]>, <[decpt]>, <[sgn]>); |
| double <[val]>; |
| int <[chars]>; |
| int *<[decpt]>; |
| int *<[sgn]>; |
| char *ecvtf(<[val]>, <[chars]>, <[decpt]>, <[sgn]>); |
| float <[val]>; |
| int <[chars]>; |
| int *<[decpt]>; |
| int *<[sgn]>; |
| |
| char *fcvt(<[val]>, <[decimals]>, <[decpt]>, <[sgn]>); |
| double <[val]>; |
| int <[decimals]>; |
| int *<[decpt]>; |
| int *<[sgn]>; |
| char *fcvtf(<[val]>, <[decimals]>, <[decpt]>, <[sgn]>); |
| float <[val]>; |
| int <[decimals]>; |
| int *<[decpt]>; |
| int *<[sgn]>; |
| |
| DESCRIPTION |
| <<ecvt>> and <<fcvt>> produce (null-terminated) strings of digits |
| representating the <<double>> number <[val]>. |
| <<ecvtf>> and <<fcvtf>> produce the corresponding character |
| representations of <<float>> numbers. |
| |
| (The <<stdlib>> functions <<ecvtbuf>> and <<fcvtbuf>> are reentrant |
| versions of <<ecvt>> and <<fcvt>>.) |
| |
| The only difference between <<ecvt>> and <<fcvt>> is the |
| interpretation of the second argument (<[chars]> or <[decimals]>). |
| For <<ecvt>>, the second argument <[chars]> specifies the total number |
| of characters to write (which is also the number of significant digits |
| in the formatted string, since these two functions write only digits). |
| For <<fcvt>>, the second argument <[decimals]> specifies the number of |
| characters to write after the decimal point; all digits for the integer |
| part of <[val]> are always included. |
| |
| Since <<ecvt>> and <<fcvt>> write only digits in the output string, |
| they record the location of the decimal point in <<*<[decpt]>>>, and |
| the sign of the number in <<*<[sgn]>>>. After formatting a number, |
| <<*<[decpt]>>> contains the number of digits to the left of the |
| decimal point. <<*<[sgn]>>> contains <<0>> if the number is positive, |
| and <<1>> if it is negative. |
| |
| RETURNS |
| All four functions return a pointer to the new string containing a |
| character representation of <[val]>. |
| |
| PORTABILITY |
| None of these functions are ANSI C. |
| |
| Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>, |
| <<lseek>>, <<read>>, <<sbrk>>, <<write>>. |
| |
| NEWPAGE |
| FUNCTION |
| <<gcvt>>, <<gcvtf>>---format double or float as string |
| |
| INDEX |
| gcvt |
| INDEX |
| gcvtf |
| |
| ANSI_SYNOPSIS |
| #include <stdlib.h> |
| |
| char *gcvt(double <[val]>, int <[precision]>, char *<[buf]>); |
| char *gcvtf(float <[val]>, int <[precision]>, char *<[buf]>); |
| |
| TRAD_SYNOPSIS |
| #include <stdlib.h> |
| |
| char *gcvt(<[val]>, <[precision]>, <[buf]>); |
| double <[val]>; |
| int <[precision]>; |
| char *<[buf]>; |
| char *gcvtf(<[val]>, <[precision]>, <[buf]>); |
| float <[val]>; |
| int <[precision]>; |
| char *<[buf]>; |
| |
| DESCRIPTION |
| <<gcvt>> writes a fully formatted number as a null-terminated |
| string in the buffer <<*<[buf]>>>. <<gcvtf>> produces corresponding |
| character representations of <<float>> numbers. |
| |
| <<gcvt>> uses the same rules as the <<printf>> format |
| `<<%.<[precision]>g>>'---only negative values are signed (with |
| `<<->>'), and either exponential or ordinary decimal-fraction format |
| is chosen depending on the number of significant digits (specified by |
| <[precision]>). |
| |
| RETURNS |
| The result is a pointer to the formatted representation of <[val]> |
| (the same as the argument <[buf]>). |
| |
| PORTABILITY |
| Neither function is ANSI C. |
| |
| Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>, |
| <<lseek>>, <<read>>, <<sbrk>>, <<write>>. |
| */ |
| |
| #define _XOPEN_SOURCE |
| #define _XOPEN_SOURCE_EXTENDED |
| #include <_ansi.h> |
| #include <reent.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include "local.h" |
| |
| char * |
| _DEFUN (fcvt, (d, ndigit, decpt, sign), |
| double d _AND |
| int ndigit _AND |
| int *decpt _AND |
| int *sign) |
| { |
| return fcvtbuf (d, ndigit, decpt, sign, NULL); |
| } |
| |
| char * |
| _DEFUN (fcvtf, (d, ndigit, decpt, sign), |
| float d _AND |
| int ndigit _AND |
| int *decpt _AND |
| int *sign) |
| { |
| return fcvt ((float) d, ndigit, decpt, sign); |
| } |
| |
| |
| char * |
| _DEFUN (gcvtf, (d, ndigit, buf), |
| float d _AND |
| int ndigit _AND |
| char *buf) |
| { |
| double asd = d; |
| return gcvt (asd, ndigit, buf); |
| } |
| |
| |
| char * |
| _DEFUN (ecvt, (d, ndigit, decpt, sign), |
| double d _AND |
| int ndigit _AND |
| int *decpt _AND |
| int *sign) |
| { |
| return ecvtbuf (d, ndigit, decpt, sign, NULL); |
| } |
| |
| char * |
| _DEFUN (ecvtf, (d, ndigit, decpt, sign), |
| float d _AND |
| int ndigit _AND |
| int *decpt _AND |
| int *sign) |
| { |
| return ecvt ((double) d, ndigit, decpt, sign); |
| } |
| |
| |
| char * |
| _DEFUN (gcvt, (d, ndigit, buf), |
| double d _AND |
| int ndigit _AND |
| char *buf) |
| { |
| char *tbuf = buf; |
| if (d < 0) { |
| *buf = '-'; |
| buf++; |
| ndigit--; |
| } |
| return (_gcvt (_REENT, d, ndigit, buf, 'g', 0) ? tbuf : 0); |
| } |