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Topic: How to generate Joint frequency distributions from a mxn Matrix
Replies: 1   Last Post: Dec 9, 2012 4:39 AM

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 S Ehtesham Al Hanif Posts: 9 Registered: 12/1/12
How to generate Joint frequency distributions from a mxn Matrix
Posted: Dec 8, 2012 4:39 PM

I have three column but i can avoid first one which has time value. In details:
Column T has value of time as second t=1:1:1400;
Column A has value of velocity/speed and it has 1400 speed values from 0(zero) to 100(hundred). In this case some velocity values repeats after uncertain interval.
Column B has value of acceleration and it has 1400 acceleration/deccelaration values from --4(minus four) to +4(four). In this case some acceleration values has repetition.

Now i want to generate a mxn matrix where every position will be a frequency which can full fill one condition from A and same time one corresponding B condition.

I subdivided velocity column into several group, such as: 0 to 5, 5 to 10, 10 to 15, 15 to 20 .........90 to 95 and 95-100.

Similarly i subdivided acceleration column into several group such as: -4 to -3, -3 to -2 ...... 2 to 3 and 3 to 4.

Then, i will count frequency such a way that it will full fill both columns same row with those condition.

As an example: if i look at the previous posts Column A. And Column B, then i have to find out how many times/frequency the below conditioned fullfilled?

If velocity range : 30 to 35 m/s and acceleration at the same time/row in -0.5 to -0.25 range ? According to example it has frequent/count 3! If velocity range same but acceleration condition changed to -0.25 to 0 then it has frequency 1.

I think this time my illustration is better as if it is possible to show you by showing picture or figure by attaching here it will be easy to explain what i am planning for!

Here I am showing an example in below links:
[URL=http://imageshack.us/photo/my-images/706/captureyt.png/][IMG]http://imageshack.us/a/img706/3983/captureyt.png[/IMG][/URL]

Ehtesham

Date Subject Author
12/8/12 S Ehtesham Al Hanif
12/9/12 Bruno Luong