2.5.7. Graph 2D “pairs”

This 2D graph consists in creating a matrix of graphs, where for the (i,j) cells with i different from j, the graph contains the scatterplot of the attribute j versus the attribute i, and for cell (i,i), the graph contains the histogram of the attribute i.

    TDataServer * tdsGeyser = new TDataServer("tdsgeyser", "Database of the geyser");
    tdsGeyser->fileDataRead("flowrateUniformDesign.dat");
    tdsGeyser->drawPairs();

Figure 2.49 Graphs of “Pairs” of the TDataServer geyser

Summary: 2D Graph

• drawScatterplot (const char* varexp, const char* selection=””, Option_t* option=””)

  Draw 2D graph with the number of points of attributes located in varexp on the background.

• drawProfile (const char* varexp, const char* selection=””, Option_t* option=””)

  Draw 2D graphic of the mean and standard deviation of each segment of “X” axis for the attributes contained in varexp.

  Tip

  The possible values of options option are:

  nclass=[0-9]*

  Specifies the number of segments in “X” axis .

  same

  Displays the 2D scatterplot below “profile”.

• drawTufte (const char* varexp, const char* selection=””, Option_t* option=””)

  Draw 2D graph of the attributes located in varexp.

  Tip

  The possible values of options option are:

  optstat

  Prints the window containing statistics in each histogram

  scatter

  Prints the scatterplot the same way as the command drawScatterplot.

• drawPairs (const char* varexp, const char* selection=””, Option_t* option=””)

  Create the matrix of graph with the attributes located in varexp.

It should be noticed that these functions have the same signature as the draw method of a TTree of ROOT.

Warning

For all these methods, the character varexp must contain either two attributes or a single character “:”