Introduction - Create First Variable


Note that DataTank has unlimited undo/redo, so you can revert to an earlier state if you make a mistake. This is helpful when following along the tutorials in DataTank.

In the main script window the top portion contains the variable objects. One way to create a variable is to select it from the Variable menu. Most of the variables correspond to a physical discretization of space. The "1D Plot" variable is thought of as a discretization of the real line. It is more general in that it can contain any collection of (x,y) pairs. This might be a slightly unexpected definition of 1D, but the logic is that the dimension of a variable is determined by where the values are defined. The dimension of the drawing window corresponds to the dimension of the variables that are drawn in that drawing context. For example the 2D Plot window is used to draw variables that have values defined in two dimensional space. It is, however, drawn as a 3D object.

The variable names need to be unique, but have no other restrictions. You can use spaces and non-ascii characters. The variable names can be changed at any time.

Inside the variable is the computational module, which can be selected from a pop-up menu. This controls how the variable is computed. Here the default module allows you to enter in the (x,y) pairs. The pairs can be specified by expressions.

The little question mark in the lower right corner brings up a help document for the selected module.

The variable is deleted by dragging it to any of the recycling bins in DataTank.

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