Arduino - Float

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## float

#### Description

Datatype for floating-point numbers, a number that has a decimal point. Floating-point numbers are often used to approximate analog and continuous values because they have greater resolution than integers. Floating-point numbers can be as large as 3.4028235E+38 and as low as -3.4028235E+38. They are stored as 32 bits (4 bytes) of information.

Floating point math is much slower than integer math in performing calculations, so should be avoided if, for example, a loop has to run at top speed for a critical timing function. Programmers often go to some lengths to convert floating point calculations to integer math to increase speed.

That being said, floating point math is useful for a wide range of physical computing tasks, and is one of the things missing from many beginning microcontroller systems.

#### Examples

        float myfloat;
        float sensorCalbrate = 1.117;

#### Syntax

        float var = val;

- var - your float variable name
- val - the value you assign to that variable

#### Example Code

       int x;
       int y;
       float z;

       x = 1;
       y = x / 2;   // y now contains 0, integers can't hold fractions
       z = (float)x / 2.0;   // z now contains .5 (you have to use 2.0, not 2)

#### Programming Tip

Serial.println() truncates floats (throws away the fractions) into integers when sending serial. Multiply by power of ten to preserve resolution.

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