DataAnalysis

DataAnalysis is a general purpose iPad App for the plotting and fitting of all types of data that can be formulated as x, y pairs. The program can be easily used by both students and professionals. It is particularly useful for quick analyses of various types of data by curve fitting, value prediction via a standard curve, and analysis of kinetic data including enzyme kinetics.

Data can be entered directly via the keyboard or imported from a text file (.txt), or a comma separated value file (.csv). In addition, data can be pasted from the clipboard.

After data entry the user has the option to average, baseline correct, and/or normalize the data before plotting and fitting.

Plotting of the data is as simple as pressing the Plot button. The axes are autoscaled and the graph is immediately ready to add to a document or presentation. The user has a variety of options to customize the graph by altering the axes, axes labels, graph title, and changing the symbol, its size and color.

Using touch and drag the user can create a selection box allowing the creation of a data subset. Once the data subset has been selected the user has two options: (1) To zoom in on the selected data. Any fitting done in this mode is global (e.g. uses all the data). (2) To zoom and perform a fitting only on the selected subset of the data.

The data can be fit to a variety of mathematical equations by non-linear regression including simple functions such as linear, 2nd and 3th order polynomials, power, exponential, and log functions.

Data can also be fit to more complex equations for such processes as radioactive decay, enzyme kinetics, 1st and 2nd order chemical reactions, as well as gaussian, logistics and surge functions. The fit can be overlaid on the data with different line widths, types and thicknesses.

Lowess Regression (LOcal Weighted regrESSion) can also be used to fit data without the need to specify a mathematical function. Not only does Lowess Regression not require a mathematical function, but also does not require parameters (non-parametric). This fitting method is used extensively to fit everything from election polling to astrophysics data, where the data have a large degree of scatter.

For many analytical situations, the data fit can be used as a standard curve to determine the value of unknowns. This analytical procedure is completely automated within DataAn