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-rw-r--r--docs/source/lang/randomseed.rst69
1 files changed, 28 insertions, 41 deletions
diff --git a/docs/source/lang/randomseed.rst b/docs/source/lang/randomseed.rst
index 3dcf4db..d0a15b7 100644
--- a/docs/source/lang/randomseed.rst
+++ b/docs/source/lang/randomseed.rst
@@ -1,73 +1,60 @@
-.. _lang-randomseed:
+.. highlight:: cpp
-randomSeed(seed)
-================
+.. _lang-randomseed:
-Description
------------
+randomSeed()
+============
-randomSeed() initializes the pseudo-random number generator,
+``randomSeed()`` initializes the `pseudorandom number generator
+<http://en.wikipedia.org/wiki/Pseudorandom_number_generator>`_,
causing it to start at an arbitrary point in its random sequence.
This sequence, while very long, and random, is always the same.
+Library Documentation
+---------------------
-If it is important for a sequence of values generated by random()
-to differ, on subsequent executions of a sketch, use randomSeed()
-to initialize the random number generator with a fairly random
-input, such as analogRead() on an unconnected pin.
+.. doxygenfunction:: randomSeed
+Discussion
+----------
+If it is important for a sequence of values generated by
+:ref:`random() <lang-random>` to differ, on subsequent executions of a
+sketch, use ``randomSeed()`` to initialize the random number generator
+with a fairly random input, such as :ref:`analogRead()
+<lang-analogread>` on an unconnected pin.
-Conversely, it can occasionally be useful to use pseudo-random
+Conversely, it can occasionally be useful to use pseudorandom
sequences that repeat exactly. This can be accomplished by calling
-randomSeed() with a fixed number, before starting the random
+``randomSeed()`` with a fixed number, before starting the random
sequence.
-
-
-Parameters
-----------
-
-long, int - pass a number to generate the seed.
-
-
-
-Returns
--------
-
-no returns
-
-
-
Example
-------
-::
+The following sketch initializes the random seed based on an :ref:`ADC
+<adc>` reading of pin 0. If this pin is unconnected, the Sketch
+should print different values to the :ref:`serial monitor
+<ide-serial-monitor>` each time it is run::
long randNumber;
- void setup(){
- Serial.begin(9600);
+ void setup() {
+ pinMode(0, INPUT_ANALOG);
randomSeed(analogRead(0));
}
- void loop(){
+ void loop() {
randNumber = random(300);
- Serial.println(randNumber);
+ SerialUSB.println(randNumber);
delay(50);
}
-
-
-See also
+See Also
--------
-
-- `random <http://arduino.cc/en/Reference/Random>`_
-
-
-
+- :ref:`random() <lang-random>`
.. include:: cc-attribution.txt