CC++Introduction to C++Learn C++

What Is A Float In C Programming?

What Is A Float In C Programming


C is one of the most powerful programming languages in the World and it’s suitable for a wide variety of uses and C++ too. Floating point variables are one of the important data types that use mostly. For example, you can allow this in different integer and string types, or you can convert string to integer too with a number of different C and C++ compiler choices. The RAD Studio and C++ Builder IDEs are extremely powerful and help you create C and C++ Software applications of all types. In this post, we have an example that shows what is a short int in C, how to convert an int to a string C, and a C++ example of how to convert an int to a string too.

As C/C++ developers we have a great selection of free C++ IDE and professional C++ IDEs. Tools like C++ Builder CEDev-C++, and even the BCC32 command line compiler. Although C++ Builder’s primary purpose is to be the best available C++ IDE which helps developers be at their most efficient and effective possible selves it is also quite capable of editing and compiling most C code thanks to C and C++ having a shared lineage.

What is a float in C programming?

In C and C++ language, float is a type specifier to define an identifier to be a floating-point datatype. In other words, float is a datatype that is used to hold real numbers in precision, it is used to represent the floating-point numbers. The float datatype is a 32-bit IEEE 754 single precision floating point number.

C and C++ has a lot of datatypes, you can create custom data types too. Generally we use,

  • int for integers
  • float or double for floating point numbers
  • char for characters
  • char arrays for strings

When we use float, float term is a Type Keyword, under the Type Specifiers.The float data type stored in the bits of bytes in memory. In programming, a signed 32-bit (4 bytes) integer variable has a maximum value of 231 − 1 = 2,147,483,647, whereas an IEEE 754 32-bit (4 bytes) base-2 floating-point variable has a maximum value of (2 − 2−23) × 2127 ≈ 3.4028235 × 1038. As you see, floating-point variables can hold wider range of numbers than a fixed-point variable of the same bits (here 32bits) width at the cost of precision. In an example, we can simply use the float type specifier to declare an integer g variable that will be used as gravity and then we can set its value to 9.81 as below,

or we can directly set its value on declaration as below,

What is a double float number in C programming?

If you need more precision, you can use double datatype in C and C++. The double datatype is a type specifier to define an identifier to be a floating-point datatype in 64bit (8 bytes) precision and used to hold and represent the floating-point numbers. It is a 64-bit IEEE 754 double precision floating point number for the value. It has 15 decimal digits of precision. For example, we can use double as below,

or we can directly set its value on declaration as below,

What is a long double float number in C programming?

The long double datatype is a type specifier (since the original 1989 C standard) to define an identifier to be a floating-point datatypes in 80bit (10 bytes) precision , and used to hold and represent the floating point numbers. It is improved by the C99 in 1999 that extended the standard library to include functions operating on long double such as sinl(), cosl(),  strtold(), etc.

For example, we can use long double as below,

or we can directly set its value on declaration as below,

What is printf function for a float in C programming? How to displaying floating numbers?

We can use printf to format floating numbers with Printf Precision Specifiers. Precision Specifiers are explained well here.
When we use floating numbers in printf() function,

  • for the float, we use “%f” in format
  • for the double, we use “%lf” in format
  • for the long double, we use “%Lf” in format

Here is an example

You can learn more about printf() function here;

What is a floating-point in C programming?

In C++ programming, we use float, double, long double datatypes a lot for the floating numbers. When we use floating numbers, we sometimes need to convert or need to see them nicely laid out, so we can compare numbers next to it or with the number under or upper of that number. Sometimes they are long, and we may need a few precisions to display them. We can set the format of numbers in display, both its integer and precision side. 

Floating-point numbers are used in the most of mathematical functions and in all trigonometric functions. They are important when you develop applications that has a lot of mathematical functions in mathematics, physics or in any engineering disciplines. In computational programming, standard mathematical equations or logics may not be as same as in programming. This happens because of the floating-point structure in the electronic architecture. Working with floating-point numbers requires understanding of the internal representation of data. Programmers must be aware of the finite precision issues:

  • For integral values (integer types), you must consider the possibility of overflow.
  • For floating-point values (single, double or extended precision), you must consider the possibility of accuracy loss.

Thus, if you are good at math and you have problems when you are using floating numbers, you may need to check this article to understand floating-point values.

What is a float in C++ programming?

In C++, floating numbers are same as above, the precision of floating numbers (float , double, long double) can be arranged by the std::precision() method We can fix the size of the display by using std::setw() method. In addition to these standard methods, we can use C++ Builder specific methods too.

Here are the examples about how to convert a float to string in C++ apps.

In C++ Builder; float, double, long double, int, short int, long int, long long int and other datatypes are the same as listed examples above as in CLANG standards. You can use them in C or C++ applications.

Although the free C++ Builder Community Edition is extremely powerful it is intended for students, beginners, and startups. If you are a regular business or do not qualify for the free community edition then you can download a free trial of the very latest full RAD Studio C++ Builder version.

C++ Builder is the easiest and fastest C and C++ IDE for building simple or professional applications on the Windows, MacOS, iOS & Android operating systems. It is also easy for beginners to learn with its wide range of samples, tutorials, help files, and LSP support for code. RAD Studio’s C++ Builder version comes with the award-winning VCL framework for high-performance native Windows apps and the powerful FireMonkey (FMX) framework for cross-platform UIs.

There is a free C++ Builder Community Edition for students, beginners, and startups; it can be downloaded from here. For professional developers, there are Professional, Architect, or Enterprise versions of C++ Builder and there is a trial version you can download from here.

Download RAD Studio 11

close

Oh hi there 👋
It’s nice to meet you.

Sign up to receive awesome C++ content in your inbox, every day.

We don’t spam! Read our privacy policy for more info.


Reduce development time and get to market faster with RAD Studio, Delphi, or C++Builder.
Design. Code. Compile. Deploy.
Start Free Trial

Free C++Builder Community Edition

About author

Dr. Yilmaz Yoru has 33+ years of coding with more than 30+ programming languages, mostly C++ on Windows, Android, Mac-OS, iOS, Linux, and some other operating systems. He was born in 1974, Eskisehir-Turkey, started coding in college and graduated from the department of Mechanical Engineering of Eskisehir Osmangazi University in 1997. He worked as a research assistant at the same university for more than 10 years. He received his MSc and PhD degrees from the same department at the same university. Since 2012, he is the founder and CEO of Esenja LLC Company. He has married and he is a father of a son. Some of his interests are Programming, Thermodynamics, Fluid Mechanics, Artificial Intelligence, 2D & 3D Designs, and high-end innovations.
Related posts
C++C++11C++14C++17Learn C++Templates

Learn How To Eliminate Pointers In Templates in C++

C++C++11C++14C++17Learn C++Templates

Learn To Export And Import Template Members From A DLL Or A Package In C++

C++C++11C++14C++17Learn C++Templates

What Is A Function Template In C++?

C++C++11C++14C++17Learn C++Templates

What Is A Class Template In C++?