---
name: "timer"
section: "3"
platform: "linux"
package: "mlpack-doc"
version: "1.0.10-1"
release: "Debian 8 (Jessie)"
platforms: ["linux"]
url: "https://new.carta.tech/timer"
---

# timer(3)

MLPACK Timers

## NAME

timer - MLPACK Timers

## Introduction

MLPACK provides a simple timer interface for the timing of machine learning methods. The results of any timers used during the program are displayed at output by the **mlpack::CLI** object, when --verbose is given:

```
$ allknn -r dataset.csv -n neighbors_out.csv -d distances_out.csv -k 5 -v
<...>
[INFO ] Program timers:
[INFO ]   computing_neighbors: 0.010650s
[INFO ]   loading_data: 0.002567s
[INFO ]   saving_data: 0.001115s
[INFO ]   total_time: 0.149816s
[INFO ]   tree_building: 0.000534s
```

## Timer API

The **mlpack::Timer** class provides three simple methods:

```
void Timer::Start(const char* name);
void Timer::Stop(const char* name);
timeval Timer::Get(const char* name);
```

Each timer is given a name, and is referenced by that name. You can call `Timer::Start()` and `Timer::Stop()` multiple times for a particular timer name, and the result will be the sum of the runs of the timer. Note that `Timer::Stop()` must be called before `Timer::Start()` is called again.

A 'total\_time' timer is run by default for each MLPACK program.

## Timer Example

Below is a very simple example of timer usage in code.

```
#include <mlpack/core.hpp>
using namespace mlpack;
int main(int argc, char** argv)
{
  CLI::ParseCommandLine(argc, argv);
  // Start a timer.
  Timer::Start("some_timer");
  // Do some things.
  DoSomeStuff();
  // Stop the timer.
  Timer::Stop("some_timer");
}
```

If the --verbose flag was given to this executable, the resultant time that 'some\_timer' ran for would be shown.