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diff --git a/docs/source/arduino/arithmetic.rst b/docs/source/arduino/arithmetic.rst deleted file mode 100644 index cbe3059..0000000 --- a/docs/source/arduino/arithmetic.rst +++ /dev/null @@ -1,104 +0,0 @@ -.. highlight:: cpp - -.. _arduino-arithmetic: - -Addition, Subtraction, Multiplication, & Division -================================================= - -Description ------------ - -These operators return the sum, difference, product, or quotient -(respectively) of the two operands. The operation is conducted using -the data type of the operands, so, for example, ``9 / 4`` gives ``2`` -since 9 and 4 are ints. - -This also means that the operation can overflow if the result is -larger than that which can be stored in the data type (e.g. adding 1 -to an :ref:`arduino-int` with the value 2147483647 gives --2147483648). If the operands are of different types, the "larger" -type is used for the calculation. - -(The specifics of these rules are beyond the scope of this -documentation; for more information, see `The C++ Programming Language -<http://www2.research.att.com/~bs/3rd.html>`_\ , by Bjarne -Stroustroup, Appendix C, especially §§C.4-C.6, or `this WikiBooks -entry on C++ type conversion -<http://en.wikibooks.org/wiki/C%2B%2B_Programming/Programming_Languages/C%2B%2B/Code/Statements/Variables/Type_Casting#Automatic_type_conversion>`_\ -. For more information on how computers represent integers, see the -Wikipedia page on `two's complement -<http://en.wikipedia.org/wiki/Two's_complement>`_\ ). - -If one of the numbers (operands) are of the type **float** or of type -**double**, floating point math will be used for the -calculation. - -Examples --------- - - :: - - y = y + 3; - x = x - 7; - i = j * 6; - r = r / 5; - - -Syntax ------- - - :: - - result = value1 + value2; - result = value1 - value2; - result = value1 * value2; - result = value1 / value2; - - -Parameters: ------------ - -**value1**: any numeric variable or constant - -**value2**: any numeric variable or constant - - -Arduino Compatibility Note --------------------------- - -Since the STM32 processor on the Maple is a 32-bit machine, the int -type overflows at a much higher value on Maple than on Arduino. In -particular, on Maple, ints do not overflow (become negative) until -they reach 2,147,483,648; on the Arduino, they overflow at 32,767. -Because of this, programs running on Maple are much less likely to run -into overflow issues. - - -Programming Tips: ------------------ - -- Know that :ref:`integer constants <arduino-integerconstants>` - default to :ref:`int <arduino-Int>`, so some constant calculations - may overflow (e.g., 200000 * 5000000 will yield a negative result). - -- Choose variable sizes that are large enough to hold the largest - results from your calculations. - -- Know at what point your variable will "roll over" and also what - happens in the other direction e.g. (0 - 1) for unsigned arithmetic, - or (0 - -2,147,483,648) for signed arithmetic. - -- For math that requires fractions, float variables may be used, but - be aware of their drawbacks: large size and slow computation speeds - (the STM32 has no floating point hardware, so all floating point - calculations have to be done in software). - -- Use the cast operator e.g. (int)myFloat to convert one variable type - to another on the fly. - - -See Also --------- - -- `libmaple_types.h <http://github.com/leaflabs/libmaple/blob/master/libmaple/libmaple_types.h>`_ - |