如何在C程序中分离这个数字-51.235

Question

I need to separate -51.235 which is in a file and put it as - , 51 , .235 my problem is that when I try to read it form the file and print it in code block i can put it as an int and float at the same time so i can subtract the int (51) and the float (51.235) and how can I separate the sign I put it as a character? this what i have so far

if (comand == 'S')
{
  fscanf(entrada, "%d %f",&y, &a);
  printf("\n\nthe separate number is: %d , %f",y,a); 
}

and it give me: the separate number is: -51 , 0.235000 (how can I eliminate the 3 zeros at the end?)

in the note pad it show:

S -51.235

Answer 1

Only few step :

1. Check if Positive , if YES : put your -
2. Your number = Absolute of your number (remove the - if positive, nothing if not).
3. Convert To int to get your number without decimal
4. to get decimal : just Substract your original Float by the Int value, result = 0.XXX

All of this in one line :

float num = -51.235555;
printf("%c %d %.3f", ((num > 0.0 ) ? ' ' : '-'), (int)num, (num - (float)((int)num)));

Answer 2

you can do it as follows:

#include<stdio.h>
#include<math.h>

int main(void)
{
  float num = -51.235;
  char sign;
  int intpart;
  float floatpart;

  sign=(num>=0.00f)?'+':'-';
  intpart=floor(fabs(num));
  floatpart=fabs(num)-intpart;
  printf("%c,%d,%g",sign,intpart,floatpart);
  return 0;
}

Answer 3

Question : and it give me: the separate number is: -51 , 0.235000 (how can I eliminate the 3 zeros at the end?)

Answer to eliminate the 3 zeros at the end?

printf("\n\nthe separate number is: %d , %.3f",y,a); 

Answer 4

#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>

char getChar(char **p){
    return *(*p)++;
}

void skipSpace(char **p){
    while(isspace(getChar(p)));//skip space char
    --(*p);//unget
}

char getSign(char **p){
    if(**p=='+' || **p=='-') return *(*p)++;
    return ' ';
}

void getNatural(char **p, char *buff){
    while(isdigit(**p))
        *buff++=*(*p)++;
    *buff='\0';
}

void getFloatPart(char **p, char *buff){
    char point;
    point = getChar(p);
    if(point != '.'){
        *buff = '\0';
    } else {
        *buff++ = point;
        getNatural(p, buff);
    }
}

void separate_float(char **p, char *sign, char *int_part, char *float_part){
    skipSpace(p);
    *sign = getSign(p);
    getNatural(p, int_part);
    getFloatPart(p, float_part);
}

int main(){
    char line[128]="S -51.235";
    char *p = line;
    char command;
    char sign, int_part[32], float_part[32];

    command = getChar(&p);
    if(command == 'S'){
        separate_float(&p, &sign, int_part, float_part);
        printf("%c,%s,%s\n", sign, int_part, float_part);//-,51,.235
        printf("%d %g\n", atoi(int_part), atof(float_part));//51 0.235
    }
    return 0;
}