# Solved: int to float

Understanding the conversion from one data type to another is a fundamental aspect of every programming language. In Haskell, a statically typed, functional programming language, data type conversions are no exception, especially when working with numeric types such as integer (Int) and floating point (Float). This article discusses the conversion process from Int to Float in Haskell, shedding light on the involved functions, computer behavior, and detailed step-by-step explanations.

## Conversion from Int to Float in Haskell

In Haskell, type conversion cannot happen implicitly. This reflects Haskell’s strongly typed nature, where variables are not interconvertible unless specified by programmers. The ‘fromIntegral’ function is Haskell’s embraced approach to manage conversions between Integral types like Int, and non-Integral types such as Float. It removes any potential loss of data by converting integers to floats, as floats have larger range.

convertIntToFloat :: Int -> Float
convertIntToFloat intValue = fromIntegral intValue

This simple code snippet defines a function `convertIntToFloat` that converts integers into floats using ‘fromIntegral’. It’s worth noting that ‘fromIntegral’ takes an Integral type value and returns a generic Num type, which Float belongs to.

## Understanding the involved functions

• fromIntegral: This function is a built-in function in Haskell belonging to the ‘Num’ class. It converts numeric types, particularly Integral types such as Int, to general number types such as Float.
• (::) Type Annotation: It’s used to specify the type of expressions in Haskell. This is particularly important in our function where we must state that ‘convertIntToFloat’ takes an Int and returns a Float.

Now that we’ve looked closely at the implementation and walked through the involved entities, let’s understand this with a real example.

## Step-by-Step Code Explanation

Say we have an integer 25 and we want to convert it to a float, we’d simply use our `convertIntToFloat` function as follows:

main = print (convertIntToFloat 25)

This would print: 25.0

Here’s how Haskell internally handles this conversion:

1. Step 1: The integer 25 is passed onto the `convertIntToFloat` function.
2. Step 2: ‘fromIntegral’ takes 25 as an input, which is an ‘Int’ (Integral type).
3. Step 3: ‘fromIntegral’ returns a ‘Num’ type. Since Float is part of the ‘Num’ class and is expected from the function (as denoted by the :: type annotation), Haskell translates this to float.
4. Step 4: The float version of 25 (25.0) is returned and printed.

## Explore more Libraries and Functions

Haskell’s strongly typed nature and extensive library support provide more ways to manipulate and convert types. Apart from ‘fromIntegral’, Haskell has ‘toInteger’, ‘realToFrac’ and more to assist with type conversion. In addition, the Haskell Platform and Libraries like ‘base’ offer numerous modules relating to number types and conversions, worth exploring for every Haskell programmer.

Diving deep into the Haskell libraries and understanding the type system creates a strong foundation for creating robust, error-free programs that manipulate complex data. Consequently, offering endless possibilities to expand a Haskell programmer’s toolbox.

Related posts: