## 3D Scatter Plot

## 3D Scatter Plot

(OP)

Hello,

I have been trying to create a scatter plot - the obvious way to create one is a surface "z" as a function of two variables "x" and "y", but that's not what I want to do. I have a 3-dimensional data set and I just want to see it. The Mathcad graph "3D Scatter Plot" isn't giving me what I am looking for.

My dataset has thousands of points. For extreme simplicity I will demonstrate my problem with 3 points, by giving you their XYZ coordinates:

1,2,3

4,5,6

7,8,9

To my mind, that is 3 points. 3D Surface Plot puts 9 points on the graph. It seems to be mistaking the row and rank of the matrix with data. If the row and rank were important, I would use that, but they aren't. Should I be using some other kind of chart to plot this?

I have reconfigured the inputs for this graph as vectors, matrices, and entered them separately as vectors for each coordinate, to no avail.

A file is attached. Mathcad 13

I have been trying to create a scatter plot - the obvious way to create one is a surface "z" as a function of two variables "x" and "y", but that's not what I want to do. I have a 3-dimensional data set and I just want to see it. The Mathcad graph "3D Scatter Plot" isn't giving me what I am looking for.

My dataset has thousands of points. For extreme simplicity I will demonstrate my problem with 3 points, by giving you their XYZ coordinates:

1,2,3

4,5,6

7,8,9

To my mind, that is 3 points. 3D Surface Plot puts 9 points on the graph. It seems to be mistaking the row and rank of the matrix with data. If the row and rank were important, I would use that, but they aren't. Should I be using some other kind of chart to plot this?

I have reconfigured the inputs for this graph as vectors, matrices, and entered them separately as vectors for each coordinate, to no avail.

A file is attached. Mathcad 13

__or earlier__, please.
## RE: 3D Scatter Plot

S&T - www.re-tug.com

## RE: 3D Scatter Plot

Anyway, thank you - I don't know why, but it works.

## RE: 3D Scatter Plot

S&T - www.re-tug.com

## RE: 3D Scatter Plot

TTFN (ta ta for now)

I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg

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## RE: 3D Scatter Plot

Jim

## RE: 3D Scatter Plot

The plot compares the measurement from a current sensor in various conditions. The current produced by the generator should be zero up to a certain speed threshold, then increase linearly at higher speeds. At different temperatures the sensor's sensitivity seems to change, but I wasn't sure. I wanted to spend 10 minutes exporting the data table from Excel to Mathcad and plot the 3d scatter to see it. Little did I expect it to take 2 hours doing consistently the wrong thing in MC. Which is about as long as it would have taken to do it normally in Excel but hey I'm still a MC fan despite its quirks.

Visualizing the data made it clear that the trends are hard to see in the hash of values from the current sensor. That in itself is annoying, and could be a good reason to choose a different sensor for this job. There may also be too much noise from something else in the system. I didn't even think of it at the time, but now I want to add at least a capacitor from Vcc to Ground on the sensor to see if that helps.

## RE: 3D Scatter Plot

Cheers

Greg Locock

New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

## RE: 3D Scatter Plot

TTFN (ta ta for now)

I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg

FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm