iucm.dist module

Module for calculating the average distance between two individuals

Functions

dist(population, x, y[, dist0, indices, …]) Calculate the average distance between two individuals
iucm.dist.dist(population, x, y, dist0=-1, indices=None, increase=None)[source]

Calculate the average distance between two individuals

This function calculates

\[d = \frac{\sum_{i,j=1}^N d_{ij} P_i P_j}{P_{tot} (P_{tot}-1)}\]

after [LeNechet2012], where \(P_i\) is the population of the i-th grid cell, \(P_{tot}\) is the total population and \(d_{ij}\) is the distance between the i-th and j-th grid cell

Parameters:
  • population (1D np.ndarray of dtype float) – The population data for each grid cell. If dist0>=0 then this array must hold the population of the previous step corresponding to dist0. Otherwise it should be the real population.
  • x (1D np.ndarray of dtype float) – The x-coordinates for each element in population
  • y (1D np.ndarray of dtype float) – The y-coordinates for each element in population
  • dist0 (float, optional) – The previous average distance between individuals. If this is given, increase and indices must not be None and population must represent the population of the previous step. Specifying this value, significantly speeds up the calculation.
  • indices (1D np.ndarray of dtype int) – The indices of the grid cells, where the population has been increased.
  • increase (1D np.ndarray of dtype float) – The increase in the grid cells corresponding to the given indices
Returns:

The average distance between two individuals.
Return type:

float