df024_Display.C File Reference

Detailed Description

Use the Display action to inspect entry values.

 
void df024_Display()
{
   // Setting up a Dataframe with some data
   unsigned long long y = 1;
   int x = 1;
   double w = 1;
   double z = 1;
   ROOT::RDataFrame df(10);
   auto d = df.Define("y", [&y]() { return y *= 100; }) // A column with ulongs
              .Define("x",
                      [&x]() {
                         return std::vector<int>({x++, x++, x++, x++});
                      })                                // A column with four-elements collection
              .Define("w", [&w]() { return w *= 1.8; }) // A column with doubles
              .Define("z", [&z]() {
                 z *= 1.1;
                 return std::vector<std::vector<double>>({{z, ++z}, {z, ++z}, {z, ++z}});
              }); // A column of matrices
 
   // Preparing the RResultPtr<RDisplay> object with all columns and default number of entries
   auto d1 = d.Display("");
   // Preparing the RResultPtr<RDisplay> object with two columns and default number of entries
   auto d2 = d.Display({"x", "y"});
 
   // Printing the short representations, the event loop will run
   std::cout << "The following is the representation of all columns with the default nr of entries" << std::endl;
   d1->Print();
   std::cout << "\n\nThe following is the representation of two columns with the default nr of entries" << std::endl;
   d2->Print();
}

 
The following is the representation of all columns with the default nr of entries
+-----+-----------+----+-------------+--------------------------+
| Row | w         | x  | y           | z                        | 
+-----+-----------+----+-------------+--------------------------+
| 0   | 1.800000  | 1  | 100         | { 1.1000000, 2.1000000 } | 
|     |           | 2  |             | { 2.1000000, 3.1000000 } | 
|     |           | 3  |             | { 3.1000000, 4.1000000 } | 
|     |           | 4  |             |                          | 
+-----+-----------+----+-------------+--------------------------+
| 1   | 3.240000  | 5  | 10000       | { 4.5100000, 5.5100000 } | 
|     |           | 6  |             | { 5.5100000, 6.5100000 } | 
|     |           | 7  |             | { 6.5100000, 7.5100000 } | 
|     |           | 8  |             |                          | 
+-----+-----------+----+-------------+--------------------------+
| 2   | 5.832000  | 9  | 1000000     | { 8.2610000, 9.2610000 } | 
|     |           | 10 |             | { 9.2610000, 10.261000 } | 
|     |           | 11 |             | { 10.261000, 11.261000 } | 
|     |           | 12 |             |                          | 
+-----+-----------+----+-------------+--------------------------+
| 3   | 10.497600 | 13 | 100000000   | { 12.387100, 13.387100 } | 
|     |           | 14 |             | { 13.387100, 14.387100 } | 
|     |           | 15 |             | { 14.387100, 15.387100 } | 
|     |           | 16 |             |                          | 
+-----+-----------+----+-------------+--------------------------+
| 4   | 18.895680 | 17 | 10000000000 | { 16.925810, 17.925810 } | 
|     |           | 18 |             | { 17.925810, 18.925810 } | 
|     |           | 19 |             | { 18.925810, 19.925810 } | 
|     |           | 20 |             |                          | 
+-----+-----------+----+-------------+--------------------------+
 
 
The following is the representation of two columns with the default nr of entries
+-----+----+-------------+
| Row | x  | y           | 
+-----+----+-------------+
| 0   | 1  | 100         | 
|     | 2  |             | 
|     | 3  |             | 
|     | 4  |             | 
+-----+----+-------------+
| 1   | 5  | 10000       | 
|     | 6  |             | 
|     | 7  |             | 
|     | 8  |             | 
+-----+----+-------------+
| 2   | 9  | 1000000     | 
|     | 10 |             | 
|     | 11 |             | 
|     | 12 |             | 
+-----+----+-------------+
| 3   | 13 | 100000000   | 
|     | 14 |             | 
|     | 15 |             | 
|     | 16 |             | 
+-----+----+-------------+
| 4   | 17 | 10000000000 | 
|     | 18 |             | 
|     | 19 |             | 
|     | 20 |             | 
+-----+----+-------------+

Date

August 2018

Authors

Enrico Guiraud, Danilo Piparo, Enric Tejedor Saavedra (CERN), Massimo Tumolo (Politecnico di Torino)

Definition in file df024_Display.C.