What does %di specifier do in C programming?

Question

%d specifier inside the printf function means that we're going to display the variable as a decimal integer and %f specifier would display it as a float number and so on. But what does %di specifier does ?

I found this specifier in this program(C program to add, subtract, multiply and divide Complex Numbers, complex arithmetic)

For example,

printf("Division of two complex numbers = %d %di",temp1/temp3,temp2/temp3);

That's just a `%d`, immediately followed by an `i`, probably to indicate the imaginary part. Only the `%d` is the format specifier, the `i` printed literally — dhke, Oct 06 '15 at 15:09
like if you write `printf("%di",a)` then first value of `a` will be printed then `i` (assuming `a` in an integer variable.) — ameyCU, Oct 06 '15 at 15:12

R Sahu · Accepted Answer · 2015-10-06T16:19:52.830

If temp/temp3 evaluates to 25 and temp2/temp3 evaluates to 15, the line

printf("Division of two complex numbers = %d %di",temp1/temp3,temp2/temp3);

will print

Division of two complex numbers = 25 15i

The i in the above format specifier prints the letter i. The %d parts print the numbers. The sole purpose of using i in the above format specifier is to print the real and imaginary parts of a complex number in a more user friendly way.

Ilya · Answer 2 · 2015-10-06T15:32:49.940

2

There is no specifier "%di". So, it works as "%d" and after it you have a letter "i" (it is standard way to print imaginary part of complex values).

So when you have a line printf("Sum of two complex numbers = %d + %di",c.real,c.img); it works this way:

It prints "Sum of two complex numbers = ",
It prints value c.real,
It prints " + ",
It prints value c.img,
And it prints "i".

edited Oct 06 '15 at 15:32

answered Oct 06 '15 at 15:09

Ilya

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Rahul Jha · Answer 3 · 2015-10-06T16:42:42.407

2

There is no such thing as %di in C ! In fact %d has been used in the code for the integer! Since you are printing a complex number Such as

4 + 5i

You need to print an 'i immediately after you print 5 hence "%di" is used "%d" and i are seen seperately by the printf function!

edited Oct 06 '15 at 16:42

answered Oct 06 '15 at 15:13

Rahul Jha

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"_are seen seperately by the compiler_": not by the compiler, but by the `printf` function. – Paul Ogilvie Oct 06 '15 at 16:40
^ Yeah to be more appropriate! Edited – Rahul Jha Oct 06 '15 at 16:43

score 0 · Answer 4 · answered Oct 06 '15 at 17:54

There is no specifier "%di" in C. It just works normally as "%d" and after it you have a letter "i" printed. Example your output would look something like this:

int temp1=8;
int temp2=10;
int temp3=2;

printf("Division of two complex numbers = %d %di",temp1/temp3,temp2/temp3);

output:Division of two complex numbers = 4 5i

What does %di specifier do in C programming?

4 Answers4