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/* 
HEADER:         ; 
TITLE:          BASIC cvd() in C 
VERSION:        1.0; 
 
DESCRIPTION:    perform BASIC cvd() function on packed double precision 
                DATA to unpack the data into a double value 
 
KEYWORDS:       unpack, BASIC,cvd, double precision; 
SYSTEM:         Xenix 3.4b, MSDOS; 
FILENAME:       ncvd.c 
WARNINGS:       compile with -dNO_PROTOTYPE if your system does not 
                support prototyping, with -dFOR_MSDOS if you are compiling 
                for MSDOS with an ANSI standard compiler. 
                Defaults assume compiling with prototypes for 
                Xenix 3.4b on Altos 2086 computer. 
 
SEE-ALSO:       ; 
AUTHORS:        Vern Martin, 449 W. Harrison, Alliance, Ohio 44601; 
                Thanks to Mike Thompson of ACT Consulting of Canton, Ohio 
                for helping me write the origninal version several years 
                ago. 
COMPILERS:      ECOSOFT ECO-C88, XENIX 3.4B STANDARD COMPILER; 
*/ 
 
#include "vernmath.h" 
 
#define WIDTH 8 
 
#define XTYPE double 
#define RETURN_CAST (XTYPE) 
 
#define KTYPE double 
 
XTYPE ncvd(string) 
char *string; 
{ 
    int i,s,e; 
    XTYPE x = (XTYPE) 1; 
    unsigned char c[WIDTH]; 
    static KTYPE k[WIDTH] = { 
        (KTYPE) 2.7755575615628914e-17, 
        (KTYPE) 7.1054273576010019e-15, 
        (KTYPE) 1.8189894035458565e-12, 
        (KTYPE) 4.6566128730773926e-10, 
        (KTYPE) 1.1920928955078125e-07, 
        (KTYPE) 3.0517578125000000e-05, 
        (KTYPE) 7.8125000000000000e-03, 
    }; 
 
/* convert chars to unsigned chars */ 
        for (i=0;i<=WIDTH-1;i++) { 
        c[i] = (unsigned char) string[i]; 
    } 
/* last char in string determines power to raise final total by */ 
    e=c[WIDTH-1]-129; 
 
/* determine sign */ 
/* next to last char determines sign */ 
    if (c[WIDTH-2] < (unsigned char) 128) { 
        s=1;  /* if it is positive, sign is 1 */ 
    } 
    else { 
        s = (-1); 
        /* make it think its positive */ 
        c[WIDTH-2] -= (unsigned char) 128; 
    } 
 
/* total first 3 chars multiplied by there respective factors */ 
    for (i=0;i