r.rst
author Oleksandr Gavenko <gavenkoa@gmail.com>
Sat, 27 Feb 2016 23:58:41 +0200
changeset 1926 71949d52fd3a
child 1927 417ffd620c12
permissions -rw-r--r--
Inspecting objects, Debugging, Generating random numbers

.. -*- coding: utf-8 -*-

===
 R
===
.. contents::
   :local:

Inspecting objects
==================

Info about object dimensions::

  length(c(1,2,3))
  dim(matrix(1:6, 2, 3))

Brief info about any object::

  typeof(str)
  str(c(1, 2))
  str(summary)

Brief info about vectors and matrixes::

  summary(1:8)
  summary(matrix(1:20, 4, 5))

Brief info on datasets and matrixes::

  names(list(colA=1, colB=2))

Debugging
=========

To mark function for debugging call::

  debug(fun, text = "", condition = NULL)
  debugonce(fun, text = "", condition = NULL)

To return function to normal execution::

  undebug(fun)
  isdebugged(fun)

Generating random numbers
=========================

For each distribution there are exists corresponding generation function, named
with prefix ``r``::

  rnorm(n, mean = 0, sd = 1)
  rt(n, df, ncp)
  rbinom(n, size, prob)
  rpois(n, lambda)
  runif(n, min = 0, max = 1)

In order to generate predictable sequences use::

  set.seed(seed, kind = NULL, normal.kind = NULL)