Does C Have Complex Data Type?


Scott Campbell

Does C Have Complex Data Type?

In the world of programming, complex data types allow us to represent and manipulate more intricate data structures. These data types are essential for solving complex problems and building sophisticated applications. However, when it comes to the C programming language, there is no built-in complex data type like in some other languages such as Python or Java.

Why doesn’t C have a complex data type?

The absence of a complex data type in C can be attributed to its design philosophy and focus on efficiency.

C is a low-level programming language that provides developers with fine-grained control over memory management and hardware-level operations. By not including a complex data type in its core library, C allows programmers to optimize their code for performance and memory usage based on specific requirements.

However, this doesn’t mean that handling complex numbers or structures in C is impossible. Programmers can create their own custom implementations or leverage existing libraries to work with complex data types.

How can we handle complex numbers in C?

To work with complex numbers in C, we can define our own structure that encapsulates both the real and imaginary parts of a number. Here’s an example:

#include <stdio.h>

typedef struct {
   float real;
   float imag;
} Complex;

int main() {
   Complex c1 = {3.0, 4.0};
   Complex c2 = {2.0, -1.0};
   Complex sum;

   sum.real = c1.real + c2.real;
   sum.imag = c1.imag + c2.imag;

   printf("Sum: %.2f + %.2fi\n", sum.real, sum.imag);

   return 0;

In this example, we define a structure called “Complex” that holds the real and imaginary parts of a complex number. We then create two instances of the Complex structure, “c1” and “c2”, and calculate their sum by adding their respective real and imaginary components.

Using libraries for complex data types

Another approach to working with complex data types in C is to utilize libraries that provide pre-defined implementations.

For example, the GNU Scientific Library (GSL) is a popular library that includes functions for complex arithmetic, trigonometry, exponential functions, and more. By including the GSL headers and linking the library during compilation, we can leverage its functionality to handle complex numbers efficiently.

#include <stdio.h>
#include <gsl/gsl_complex.h>
#include <gsl/gsl_complex_math.h>

int main() {
gsl_complex c1 = gsl_complex_rect(3.0);
gsl_complex c2 = gsl_complex_rect(2.0);
gsl_complex sum;

sum = gsl_complex_add(c1, c2);

printf("Sum: %.2fi\n", GSL_REAL(sum), GSL_IMAG(sum));

In this code snippet, we include the necessary headers from the GSL library and use the predefined complex type "gsl_complex" provided by the library. We can then perform operations on complex numbers using the GSL functions, such as adding two complex numbers together.

The resulting sum is accessed using the "GSL_REAL" and "GSL_IMAG" macros.


Although C does not have a built-in complex data type, it doesn't limit us from working with complex numbers or structures. By defining custom structures or utilizing external libraries like GSL, we can handle complex data efficiently in C. The flexibility and control offered by C make it a powerful language for dealing with intricate programming tasks.