How do I read in and plot 3D data?

Question

After reading the documentation, this was my first attempt:

import ["C:\\...\\pfc.dat", "Table"]
ListPlot3D[Table];

I get "arrayerr::Table must be a valid array or list of valid arrays".

The data is formatted like x,y,z e.g. 0,1,0.9

I realize this is simple but I don't understand why it is failing.

Answer 1

It looks simply like a syntax error. First of all, in MMA all commands are upper case, so you should do

data=Import["C:\\...\\pfc.dat","Table"]

Note a lack of space between Import and ["C:\\...\\pfc.dat","Table"].

Second, you want to plot a set of points, so instead using ListPlot3D you should use ListPointPlot3D.

Finally, you used Table as an argument of the plotting function, but as emphasized above, it is a built-in command. You should type

ListPointPlot3D[data]

possibly with any options you want - see @cyrille.piatecki's answer for an example.

Answer 2

As you are clearly a beginner I will decompose the process.

I suppose your file look like this one

 457.81 ,208.16 ,68.02
 46.71  ,8.69   ,2.99
 1198.97    ,195.99 ,3.99
 30.94  ,21.78  ,5.94
 4.43   ,6.64   ,4.95
-54.04  ,7.3    ,7.72
 127.70 ,42.76  ,6.22
-695.26 ,138.14 ,35
-226.36 ,4.98   ,8.33

you will see that the end of line is not specifically marked so one must provide to Mathematica the way to understand it.

Whichever be placed your file, you can load it with

l = ToString[Import["C:\\mypath\\data.txt"]]

This command read the file and transforms it in a string then we give a name to this string.

Now we want a string that looks like a List

l1 = StringSplit[l]

Unfortunately, this leads to the apparition of a not desired patern (, ,) To eliminate it we replace it

l2 = StringReplace[l1, "," -> " "]

Then we want to reconstruct a table

l3 = Partition[l2, 3]

To finish we need to comme back to an expression because we want to plot it

l4 = ToExpression[l3]

You can observe that it is a matrix of 3 columns so one can plot it

ListPointPlot3D[l4, 
PlotStyle -> {Directive[GrayLevel[0], Opacity[0.406]], 
PointSize[0.05]}, Filling -> Bottom, ColorFunction -> "Rainbow"]

Hope this fulfills your hopes.