Menu: Geometry->Create->Parametric line
Tool to create a parametric approximated curve
The data that must be input are the mathematical formulae of the coordinates X(t), Y(t) and Z(t), where 't' is the parameter of the curve, and its value belongs to the interval [ t0-t1 ]. The curve is created by approximation and is a NURBS (Non-Uniform Rational B-Spline) which is created with N points. In GiD these kinds of curves are cubic (order 3).
The valid mathematical funcions are all Tcl functions:
We fill the formula bars with the expression of a conic helix.
That helix starts with radius R0=4 and finishes with radius R1=1, performing N=3 turns from t=0.0 to t=1.0, the height also changes from 0 to H=5.