[ROOT] ncolors and Draw("colz")

From: Alexandr Malusek (Alexandr.Malusek@imv.liu.se)
Date: Tue Oct 29 2002 - 20:33:27 MET


Hi,

I have a problem with setting the number of palette colors when the
"colz" option is used with TH2. In the past, the following code set 32
colors but now only 20 colors are displayed on the color bar.

// A palette problem
{
  const Int_t colNum = 32;  
  TH2S *h = new TH2S("h", "h", 10, 1, colNum, 10, 1, colNum);

  Int_t palette[colNum];
  for (Int_t i=0;i<colNum;i++) {
    TColor *color = new TColor(301+i,
			       pow(i/((colNum)*1.0),0.3),
			       pow(i/((colNum)*1.0),0.3),
			       0.5*(i/((colNum)*1.0)),"");
    palette[i] = 301+i;
  }
  h->SetMinimum(1);
  h->SetMaximum(colNum);
  gStyle->SetPalette(colNum,palette);
  h->Draw("colz");
}

I need 58 colors to distinguish tissues in some low resolution medical
images. How can I do it?

--
Alexandr.Malusek@imv.liu.se



This archive was generated by hypermail 2b29 : Sat Jan 04 2003 - 23:51:16 MET