CODEWITHSUNDEEP
c
Akash Sharma
Akash Sharma

Reputation: 801

Format Specifies in C for float datatype

int main()
{
    system("color FC");
const float i=23.1234234;
printf("%5.4f",i); 
getch();
return 0;
}

In above code , while printing float data type %5.4 format specifier is used. I understood that .4 is used to get four numbers after decimal but whats the use of 5 before .4

Upvotes: 0

Views: 5137

Answers (3)

haccks
haccks

Reputation: 106122

5 is used to right justify the output by 5 places. Since the output is 10 character long so the effect is not seen. Now try this 

#include <stdio.h>
int main()
{
const float i=23.1234234;

printf("%f\n",i);
printf("%5.4f\n",i);
printf("%7.4f\n",i);
printf("%10.4f\n",i);
printf("%12.5f",i);

return 0;
}

Output: 

23.1234234
23.1234
23.1234 
    23.1234
      23.1234

Upvotes: 0

Rafed Nole
Rafed Nole

Reputation: 122

5 is used to right justify the output by 5 places i.e. the last digit will occur 5 places from cursor's initial position, if possible.

It is effective only when the length ( including the decimal ) is smaller than what is mentioned in the specifier.

e.g. printf("%5.4f",i);

till the specifier at the place of 5 is smaller than or equal than the length of the output

i.e 2(before decimal) + 4(after decimal, as chosen ) + 1 (the decimal itself) =7 , it has

no effect.

It will have effect here if it is at least 8.

At 7 it does what it should but you won's see any spaces.

Upvotes: 1

Paul Draper
Paul Draper

Reputation: 83411

The 5 is the length specifier. In this case, the printed float will take up at least 5 spaces. If it is shorter than that, leading spaces will be used.

(Though because of the precision 4, it will always be at least 6 characters long; the length modifier 5 in this case is a no-op.)

See documentation.

Upvotes: 2

Related Questions