DataGraph is a combination of statistical tool, visual data exploration and a drawing program. You can enter in data, import data from huge text files or Excel spreadsheets, modify manually or massage using arbitrary expressions and numerical methods. You can compute statistics such as function fits, multivariate fits, histograms, box and whisker. DataGraph has a really powerful pivot action that allows you to drill into the data and slice and slice it to explore the data. You can create publication quality graphs with easy and control every aspect of the graph or let DataGraph handle it for you. Export as bitmaps or pdf/eps/svg vector graphics. DataGraph allows you to manipulate tens of millions of data values in real time, with changes done live as you vary sliders and select menu options. A free trial is available from the DataGraph web site, so it is easy to see it for yourself before you purchase. Be sure to view the manual that is available through the Help menu, and ask questions by mail or on the discussion board. DataGraph is created by the same company that made DataTank, a high end scientific application which won the Apple Design Awards in 2005 as the best Mac OS X Scientific Computing Solution. Source.