.. highlightlang:: us

.. index:: std

.. _std:

std
===

.. us.tag  std ENGLISH New5111  math-base

:ref:`std` returns the standard deviation of its parameter.

.. function::  rsSigma = std(rvVect)
               rsSigma = std(rvVect, flag)

.. us.return

**Return Value**

*rsSigma* is the standard deviation of the vector *rvVect*.

.. us.params

**Parameters**

.. uparam:: rvVect

   *rvVect* is a real vector.

.. uparam:: flag

   If *flag* is set to 0, the data is normalized by n-1 (default); 
   If *flag* is set to 1, the data is normalized by n; 

.. us.example

**Example**

::

   * std([5,6,12,24])
     8.7321

.. seealso::
   :ref:`overview-mathematic`,
   :ref:`sum`,
   :ref:`mean`,
   :ref:`cov`,
   :ref:`corrcoef`,
   :ref:`quantile`

:sub:`id-1488013`