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+.. highlight:: cpp
+
+.. _lang-include:
+
+``#include``
+============
+
+``#include`` is used to include outside libraries in your sketch.
+This gives the programmer access to a large group of standard C
+libraries (groups of pre-made functions and data types), and also
+libraries written especially for Maple.
+
+Example
+-------
+
+This example (from the `Arduino LiquidCrystal Tutorial
+<http://arduino.cc/en/Tutorial/LiquidCrystal>`_) includes a library
+that is used to control :ref:`LCD displays
+<libraries-liquid-crystal>`::
+
+ // include the library code:
+ #include <LiquidCrystal.h>
+
+ // initialize the library with the numbers of the interface pins
+ LiquidCrystal lcd(12, 11, 5, 4, 3, 2);
+
+ void setup() {
+ // set up the LCD's number of columns and rows:
+ lcd.begin(16, 2);
+ // Print a message to the LCD.
+ lcd.print("hello, world!");
+ }
+
+ void loop() {
+ // set the cursor to column 0, line 1
+ // (note: line 1 is the second row, since counting begins with 0):
+ lcd.setCursor(0, 1);
+ // print the number of seconds since reset:
+ lcd.print(millis()/1000);
+ }
+
+Note that a ``#include`` line, like :ref:`#define <lang-define>`,
+has **no semicolon**. The compiler will print strange error messages
+if you add one.
+
+C Standard Library
+------------------
+
+The standard C library that comes with Maple is called `newlib
+<http://sourceware.org/newlib/>`_. Its main sources of documentation
+are its `main reference <http://sourceware.org/newlib/libc.html>`_
+page and its `math functions
+<http://sourceware.org/newlib/libm.html>`_ reference page. Here's an
+example that imports the math.h library in order to take the `cube
+root <http://en.wikipedia.org/wiki/Cube_root>`_ of a number::
+
+ #include <math.h>
+
+ void setup() {
+ // no setup necessary
+ }
+
+ void loop() {
+ // "cbrt" stands for "cube root"
+ double cubeRootOf3 = cbrt(3.0);
+ // prints a number that is approximately the cube root of 3:
+ SerialUSB.println(cubeRootOf3);
+ }
+
+
+
+.. include:: cc-attribution.txt