handle input files that contain bad lines

example:

2014-03-27T12:30:24.093954,0.450437784195,0.0
2014-03-27T12:30:24.475199,0.381160020828,0.0
2014-03-27T12:30:24.877568,0.402286052704,0.0
2014-03-27T12:30:25.255715,0.378062963486,0.0
2014-03-27T12:30:25.499678,0.2438788414,0.0
2014-03-27T12:30:25.499678,