This function takes in a vector of numbers denoting the breaks in partition of an interval and returns a list of indeces that correspond to indeces that are contained within an individual intervals. The individual parts then contain (a,b] for all pairs in the interval. Hence if you want pi to be included, the partition should start with something slightly bigger than pi.
getPartition(partition, n.ahead)
breaking points of partition of frequency interval, should be ordered decreasingly.
how many observations is the FFT done on.
a list of vectors of indeces corresponding to individual partitions