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diff --git a/docs/source/arduino/float.rst b/docs/source/arduino/float.rst deleted file mode 100644 index 2f83a67..0000000 --- a/docs/source/arduino/float.rst +++ /dev/null @@ -1,88 +0,0 @@ -.. _arduino-float: - -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. - - - -Floats 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. Unlike other platforms, where you can get more precision by -using a double (e.g. up to 15 digits), on the Arduino, double is -the same size as float. - - - -Floating point numbers are not exact, and may yield strange results -when compared. For example ``6.0 / 3.0`` may not equal ``2.0``. You -should instead check that the absolute value of the difference -between the numbers is less than some small number. - - - -Floating point math is also 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. - - - -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, ints can't hold fractions - z = (float)x / 2.0; // z now contains .5 (you have to use 2.0, not 2) - - - -See Also --------- - - -- `int <http://arduino.cc/en/Reference/Int>`_ -- `double <http://arduino.cc/en/Reference/Double>`_ -- `Variable Declaration <http://arduino.cc/en/Reference/VariableDeclaration>`_ - |