Make functions to create the A / Coverage matrix

[njtierney]

Consider the example that you have a dataframe containing the GPS co-ordinates of Cardiac Arrest locations, and another data frame of possible locations to place AEDs that could be used in a Cardiac Arrest.

This function / these functions would do the following:

• Calculate the euclidean distance matrix (D) that calculates the distance between every possible location and each cardiac arrest, potentially using rnoaa::meteo_spherical_distance
• Create a binary (TRUE/FALSE or 1/0) matrix where a given cell is TRUE if the distance is less than some ideal number (say 100m, or 200m).

[njtierney]

Oh man, smashed this out today.