Homework Help: Need help with 3D charting

1. Feb 17, 2010

rmichaels

Greetings:

I am trying to help my son graph some data for a colorful 3D lattice or point distribution chart to display for a science fair project. We measured magnetic flux with a hall sensor on an x,y,z axis pedestal.

We took data from measurements of cartesian coordinates in 3 dimensions -- actually 4 planes of 9 X 9 grid each plane (20mm distance vertical each plane, gives one at 20 mm height, 2nd at 40mm height, 3rd at 60mm and 4th at 80mm.

Also all the data points on these planes were 20mm distance from each other as well.

If you go to http://www.exoticdigital.com/Magnetic_Array.html

and scroll all the way to the bottom of this webpage - - -this webpage shows a screenshot of the graphing program and one of the 4 datasheets - - the view on the datasheet is as though you were looking from above down at the magnet array lying on the table with the "working end" of the magnet array facing upwards.

I am calling the Z axis and X axis on the same plane and the Y axis the vertical looking from the top down - - is this correct ?

I am trying to use some freeware program called 3D Grapher from Romansoft labs since it allows the entry of specific data points. Most of the other software I looked at cost money or the demo versions don't cooperate.

Many graphing programs only use mathemathical formulas to generate graphs, so they are not useful to us.

My question is this: Can you help me understand how I should enter this data properly in the table (attached also).

I am not able to understand where 1,1 data, the 1,2 data, the 1,3 and so on and so forth should be entered, etc.

My data shows 1,195 gauss at the origin, and 913 just above it. Can you show me for several of the measurements what the corresponding coordinates should be so I can understand how to properly enter the data for all 3 axis X,Y and Z?

Regards,

2. Feb 18, 2010

LCKurtz

Assuming you place the planes on top of each other, a 3D picture would use up all three dimensions just plotting the points. How are you planning to show the intensity of the field at each point? Perhaps plotting each point in a part of the color spectrum -- something like a scale going from light blue to bright red, depending on the magnetic intensity, or something similar?

3. Feb 19, 2010

sarbot

All my measurements are 20 mm apart on 3D cartestsian coordinates, so I decided to define Z as 20 for all Z datapoints for the 1st plane, and Z=40 for all Z datapoints Z in the second plane, and so on, and that for each data set I define an X,Y coordinate like 0,0 as the origin, and then -1,0 is the coordinate one step to the left, etc.

Each of the 4 planes is 9 X 9 datapoints.

So I assume I would have 0,0,20 as the origin on the 1st plane (0,0 is the absolute center of the grid).

But, so far, not one "expert" can tell me where I place the measurement value in gauss in each datapoint ?? For example the 0,0 origin in my data grid has gauss reading of 1,195. Where does that go ?

0,0,20,1195 ?????

Somewhere the data needs to have the gauss measurement so the chart can plot the relative strength of the gauss data - - the X,Y,Z only gives the coordinates so the software then knows what color to chart the magnet flux strength at that coordinate point, like say deep bright red anything over 1000 gauss, moving down to light orange anything around 500 gauss, and yellow anything around 250 gauss, etc. etc.

This is what I need the chart to do, the X,Y,Z is only coordinate location data so the graph software knows where to show (with color graduations) the relative gauss strength measurements.

So far, nobody has a charting program that supposedly allows this . . . . I'm like WHAT ? Your charting/graphing programs are all just for abstract "tooling" around ? How do real scientists chart and display their data then ?

If you scroll down to the bottom of this webpage below you'll see the my datapoints for the 1st plane:

http://www.exoticdigital.com/Magnetic_Array.html

4. Feb 19, 2010

LCKurtz

You might want to go easy on the "experts" criticism thing. People helping in this forum can be anything from students currently taking classes to graduate students to professors, both active and retired. What they have in common is that they are all volunteering their time to help others.

That is exactly why I replied to you, wondering whether you wanted to represent the flux by a color hue, since the 0,0,20 uses up the 3D coordinates.

Most software of this type is general purpose. Maybe there is something that is set up to do exactly what you want but maybe not, at least not for free. More than likely whatever software that is used will require some programming, even if for nothing more than converting your data into color information.

I play around with Maple a bit, and with a little programming, it can be made to do what you want. For example, just fooling around with it a bit this morning, I created the following plot, illustrating two planes of data (not your data; just experimenting). Here's what it looks like going from blue to red as it moves in one direction.

http://math.asu.edu/~kurtz/pix/flux.gif [Broken]

If you want to pursue this, I can help you. I will need to give you a format in which to send me the data. By the way, it appears your data has some negative values for the flux. Am I reading it right?

Last edited by a moderator: May 4, 2017
5. Feb 21, 2010

LCKurtz

Sarbot or michaels, this is a reminder that I can plot your data for the science fair project. If you would like me to do that you need to contact me so I can arrange for you to send me the data readings. To do so, use the email address kurtz@asu.edu.invalid but leave off the .invalid suffix.