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.. highlight:: cpp
.. _arduino-float:
float
=====
.. TODO move all the useful examples over to arduino/double.rst. We
.. want to discourage using floats, since most of the common cmath
.. functions are only declared with doubles.
Description
-----------
Single-precision floating point number. ``float`` values 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.
``float``\ s have only 6-7 decimal digits of precision. That means the total
number of digits, not the number to the right of the decimal point.
You can get more precision by using a :ref:`double <arduino-double>`
(which has a precision of about 16 decimal digits).
The following example declares a ``float`` value named ``myfloat``::
float myfloat;
This example declares a ``float`` value named ``sensorCalibrate``,
with value 1.117::
float sensorCalibrate = 1.117;
The general syntax for declaring a float named ``var`` with value
``val`` is::
float var = val;
Here is a more extended example involving a :ref:`float cast
<arduino-floatcast>`::
int x;
int y;
float z;
x = 1;
y = x / 2; // y now contains 0, ints can't hold fractions
z = float(x) / 2; // z now contains .5
See Also
--------
- :ref:`int <arduino-int>`
- :ref:`double <arduino-double>`
- :ref:`Variables <arduino-variables>`
.. include:: cc-attribution.txt
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