Velocity profile from 3d velocity space data

AI Thread Summary
The discussion focuses on analyzing a dataset of velocity components in three-dimensional space to create a two-dimensional plot of velocity distribution. The user, Jimbo, successfully implemented shell binning to determine the density of velocity components as a function of radial distance, revealing a probability distribution that decreases with increasing velocity. He offers to share his results and methodology for others facing similar challenges. Another user, Mohamed, expresses interest in Jimbo's approach and requests the method and results. The conversation highlights the importance of effective data visualization techniques in understanding velocity distributions.
jimbo_durham
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Hi. I have a load of data objcts, each with velocity components in the cartesian x,y,z directions. I would like to find a measure of the distribution of velocity (assuming it is averaged in all directions - a good assumption). Ie i would like to end up with some 2d plot with velocity along the 'x' axis, and number density, propability amplitude etc up the 'y' axis.

I have plotted the velocity data in 3d to show the distribution in x,y,z. it is attached. It appears that the velocity falls off in probability as 1/r^2 or similar. ie there are lots of objects with velocitys in the low 10s of kms-1, and fewer objects in the high 100s kms-1. I have the raw data and need find the form of the function.

Basically, from the plot in the figure, i need the density of dots(representing velocity componants) as a function of radius. How can i do this from the raw data? i think this might be a binning problem, where the bins are shells with equal volume in velocity space, and the number of 'dots' which fall into the shell gives the form of the function i am after.

any better ideas?

thanks in advance
jimbo
 

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solved. shell binning worked fine. alhough the volume of each shell was allowed to change, this was accounted for and the number density found as a function of radial distance from center, equating to a number density profile against actual velocity.

thanks to anyone who read this and was thinking of a solution for me
 
ps if anyone wants to see the results/method if they are doing anything similar, i can post them
 
jimbo_durham said:
ps if anyone wants to see the results/method if they are doing anything similar, i can post them

Dear Jimbo,
may be i have more complicated problem, but i believe your example would help me much, please send me the method and results to [email address deleted]

Best Regards,
Mohamed
 
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