m1, m2etc. refer to a particular dataset added to the chart.
nis a float value.
periodis an integer value defining the number of trailing data-points considered by the function, applied to the data resolution specified (i.e. a simple moving average with period 30 will consider 30-days for daily resolution data, and 30-weeks for weekly resolution data).
sinceis a timestamp in format
"YYYY-MM-DD HH:mm:ss"(quotations required in syntax). Timestamps can be shortened from left to right, for example
"2010"will resolve from 01-Jan-2010 onwards, and
"2010-06"will resolve from 01-June-2010 onwards.