**3.4. Temperature update**

The most common cooling schedule is the geometric rule for temperature variation:

$$T\_{i+1} = \exp\left(\frac{\log\left(\text{stop}\_{temp} / \text{start}\_{temp}\right)}{n\_{temp} - 1}\right) T\_i \tag{3}$$

where *stoptemp* and *starttemp* are the final temperature (standard deviation) and the initial temperature, respectively, and *ntemp* is the number of temperatures considered. However, other schedules have been proposed in the literature [19]. Another parameter is the number of iterations for each temperature, which is often related with the size of the search space or with the size of the neighbourhood. This number of iterations can even be constant or, alternatively, can be defined as a function of the temperature or based on a feedback from the process [18].
