Charting a Frequency Distribution

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From: Mark Schreiber (anonymous_at_discussions.microsoft.com)
Date: 05/31/04 

Date: Mon, 31 May 2004 13:46:05 -0700

Greetings, math and Excel wizards! Looking for an idea on how to convert random data into bins of magnitude vs frequency of occurrence, then chart the data. Specifically:
1. Data: Electrical demand values for a manufacturing facility, in 15-minute intervals, for an entire month. Data is basically a time-marked stream of kilowatts vs date/time.
2. Goal: Create a data set and corresponding chart of kilowatts vs frequency of occurrence. The abscissa will be frequency of occurrence, from 1 (where the single, maximum peak value occurs) to several hundred. The ordinate will be the kilowatt value, or perhaps a bin containing kilowatt values between two values. I envision there will be a single, maximum peak value at the y-axis, then a decreasing function. Mathematically, this is somewhat like a Fourier transform used in vibration analysis, where you take a signal of amplitudes in the time domain and transform it into the frequency domain to identify vibration at significant frequecies.

Any suggestions would be greatly appreciated. Thanks.

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