prime XY plot

Hi

Issue 1
"the only reason I'm putting up with prime is that I do have a large data set and MC15 can't handle that many dots. In prime I noticed that once I've changed the trace colour, it became "uneditable"; i.e. I can't change neither colour nor line thickness anymore. Is it just me or a prime bug? and - does anybody know a workaround?"

Answer 1
Both forms of creating a 2D graph in Prime at 1,500,000 points you can edit the colour and thickness on my system. In the chart component you need great patience for the editor to come up and changes to come into effect once made.

Issue 2
"I have a similar problem, too much data. The data needs to be plotted using a scatter diagram. The Prime scatter data is plotted as black dots. There is also not control in the orientation of the axis's. I want to look down on the X and Y axis. Prime also only allow using the mouse to set the orientation."

Answer 2
Simply plot the X and Y components of the 3D data in a 2D scatter plot.

Issue 3
"my sample size is close to 1.5*10^6 points. And I'd like to compare two of them side by side in a graph. Is there a way to read in only every second data point? That way I'd have to handle less." & "I'm aware of using a routine to reduce the number of points to be handled (I've written one). However, I'd like to reduce them already when reading in so that there are less points to start with. I've seen this in Origin where you can choose how many or in which order to read in; say only every second point."

Answer 3
Mathcad cannot parse a large file line by line or data element by data element it reads in vectors/matrices. You can however in the programmable function that splits large data into say every second point put the commands to read the main data file. This means the large amount of memory for the large data set only exist during running of the programmed function.

Plotting large data sets.  Here is the path of an optimisation technique.  It is slow needing millions of points.  Mathcad handles the technique but not the plot.  Done in scilab [It is free software].  Over 3,000,000 million blue points and one red point at solution in upper left corner in last swirl.

Cheers