Data Input Q&A¶
How do I input data while simultaneously graphing it?¶
Use the TableCurve Editor option in the Edit menu and activate the Graph button after 3 or more points have been entered.
How do I reverse the X and Y values?¶
This can be done in the TableCurve Editor using the Reverse XY button.
Although TableCurve 2D sorts the data by ascending X, is there a way to save the data unsorted or in some other sort order?¶
TableCurve 2D automatically sorts the data by ascending X when exiting the TableCurve Editor. To save the data as it is entered, or for a different sort order, the data must be saved from within the TableCurve Editor. The editor contains a Sort Table option which can be based on either X or Y, and which can be either ascending or descending.
My X values are equally spaced. Do I need to enter each of these?¶
Turn on the AutoEntry X in the TableCurve Editor. After two X values have been entered, all subsequent entries will be automatic.
Can I have a transformation applied after entering X or Y values?¶
Use the Calculation option in the TableCurve Editor to enter the transform. Be sure Apply New is checked.
Can I enter or edit the data table using a simple ASCII editor?¶
Use the ASCII Editor option in the Edit menu.
What is the best way to assign weights to data?¶
Weighting of fits is used to compensate for a variety of factors. The most common is to weight the data based upon uncertainty. When each point represents the average from multiple observations, weights are generally set to inverse variances (1/SD²). When each point represents a single observation, the weights can represent a measure of experimental uncertainty for that element of the data.
Weighting is sometimes used to compensate for limitations within the least-squares process, especially when the Y values span several orders of magnitude or more. It is often simplest and most effective, however, to apply a Y=LN(Y) calculation prior to fitting rather than using weighting.
How do I generate data?¶
Use the Generate Data option in the Edit menu to automatically generate a data set from a set of mathematical expressions. Gaussian noise can be automatically added.