Real plane: Plane curves
In addition to functions of the type y = f(x), which assign exactly one abscissa value to each ordinate value, CGRAPH can also display curves in which both the x and y coordinates are functions of a parameter. With this definition, any shape can be drawn in two-dimensional space.
For plane curves, the availability of variable names in the function editor is limited to x and t, which can be used as synonyms for each other. The variable x or t is therefore no longer identical to the abscissa coordinate x - we therefore recommend always using the variable t. Only functions that contain the variables x, t and param are therefore permitted. Enter the desired function in the input field for the function, or select one of the existing functions by clicking on the arrow to the right of the input field.
If the function is only available as an implicit equation of the form f(x,y) = 0, the graph type Implicit Functions can be used instead.
CGRAPH displays flat curves within the range specified for the variable.
After clicking on the Create graph button, CGRAPH switches to the Display tab and displays the graph.
The default values can be viewed in the tree on the left-hand side. Clicking on the (optional) parameter also activates the parameter's adjustability at the bottom. An explanation of this function can be found in the notes on changing the parameter in the graphic display.
The curve shown here is a Pascal's screw. The default values can be changed retrospectively – clicking on one of the values switches CGRAPH back to the tab with the default values. The graphic is adjusted as soon as the Create graphic button is clicked. Clicking on the coloured symbol for the graph allows you to quickly hide the graphic from the display. Double-clicking on the text allows you to adjust the graphical representation.