The start- and end-points are used for dividing the data into batches.
makeStartEndPoints(batchSize, numRows)
Desired batch size
Number of rows of the data
If the data is not divisible by the batchSize
the last batch
will contain the rest of the data.
The function returns a list with in which the first entry is a list with the
values for the start and end points for reading the data matrix. The second
entry is the number of batches.