Contour plot of grided data

ROOT
1

Hi,

I’m interested in reproducing the attached plot (WP-trapezoid.png - generated with an E&M solver) using ROOT. The data (temp.csv) are a grid of 6000+ points (-5.5<x<5.5, -20<y<20) whose z values are bounded (0<z<1). I simply want to color code my grid and add contours (say green for 0.9 < z < 1., etc). This is not a histogram that I am creating so after studying the tutorials I attempted generating a scatter plot using TGraph2D, viz (omitting the contours for the time being)

#include <TRandom.h>
#include <TStyle.h>
#include <TCanvas.h>
#include <TF2.h>

void stevefit()

{
TCanvas *c1 = new TCanvas(“c1”,"",0,0,600,400);
TGraph2D *dt = new TGraph2D(“temp.csv”);
gStyle->SetPalette(1);
dt->Draw(“surf1”);

}

However, the result (results_with_ROOT.png) is always the same - the values for z are all identically zero. Obviously I am missing the boat here, perhaps by a long shot…

Thanks,

Steve


WP-trapezoid.png927×665 83.5 KB

temp.csv (193 KB)

2

Try (note that all data points seem to lie on a very thin vertical plane): root [0] TGraph2D *dt = new TGraph2D("temp.csv"); root [1] dt->Draw("P");

3

Thanks Wiley,

I had stumbled across that myself but without contours I wasn’t convinced I was on the right track…Can you point me to a tutorial or post that would faciliate the process of adding contours to the attached plot?

Thanks,

Steve


Thanks Wiley,

4

There nothing in ROOT doing the color plot you posted (i.e. a contour plot in a plane in 3D).