Distance Calculation Tool

Task is pretty quick eplained: I need a tool which i can feed with a large xml file with about 15000 entrys like: (...)<coordinates>-66.362562,50.192637,0 -64.487000,49.886492,0 -64.154664,49.930575,0 -61.732178,50.015100,0 -60.012818,50.131078,0 -55.903931,51.633619,0 -9.522400,51.374614,0 -9.824524,51.395116,0 -5.745849,50.000750,0 -5.196533,49.902011,0 0.263671,50.684201,0 1.928100,50.988498,0 2.334594,51.031561,0 2.172801,51.021948,0 2.167406,51.008807,0</coordinates>(...) the tool calculates then the distance from first to last point (going over the points in between) and adds <distance>XXX</distance> into every entry of the xml file. cant be done with excel, as of its limitations in table and cell size.