Path: news.mathworks.com!newsfeed-00.mathworks.com!solaris.cc.vt.edu!news.vt.edu!news.glorb.com!npeer01.iad.highwinds-media.com!news.highwinds-media.com!feed-me.highwinds-media.com!post01.iad.highwinds-media.com!newsfe21.iad.POSTED!7564ea0f!not-for-mail
From: Walter Roberson <roberson@hushmail.com>
User-Agent: Thunderbird 2.0.0.24 (Macintosh/20100228)
MIME-Version: 1.0
Newsgroups: comp.soft-sys.matlab
Subject: Re: How can I find the mean between to points of normal distribution?
References: <i371ts$ht3$1@fred.mathworks.com>
In-Reply-To: <i371ts$ht3$1@fred.mathworks.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
Lines: 9
Message-ID: <PfE5o.51090$dx7.6397@newsfe21.iad>
NNTP-Posting-Host: 24.79.143.47
X-Trace: newsfe21.iad 1280774255 24.79.143.47 (Mon, 02 Aug 2010 18:37:35 UTC)
NNTP-Posting-Date: Mon, 02 Aug 2010 18:37:35 UTC
Date: Mon, 02 Aug 2010 13:37:35 -0500
Xref: news.mathworks.com comp.soft-sys.matlab:658393

BobC Cadenza wrote:
> Given a normal distribution with mu,sigma.  How can I find the mean 
> between two points?  So for example I want to find the mean value 
> between -.5 *sigma to +2 sigma?

cdf() to +2 sigma, minus the cdf() to -1/2 sigma.

This is, of course, exactly equivalent to integrating the pdf between 
-1/2 sigma and +2 sigma.