Use the 2D-plot window Insert > Plot command, click on the icon on the command toolbar, or press the F4 key to plot the expression highlighted in the algebra window associated with the 2D-plot window.  The file 2D-plotExamples.dfw in the Users\Plotting directory includes several expressions that are interesting to plot in a 2D-plot window.


The Insert > Plot command is available only if there is a highlighted expression in the algebra window.  The highlighted expression will be plotted using the next plot color (see the Options > Display > Plot Color commandJDDXSP).  If you wish to stop the plotting before completion, press the Esc key.  


The type of plot made is based on the form of the expression being plotted as follows:

•        Explicit function plots are made when plotting equations of the form y = u, where y is a variable and u is a constant or a univariate expressionUnivariate_expression independent of y (for example, y=2·x+3, y=SIN(x), and x=SIN(y)).  Explicit plots are also made when plotting nonequations of one or no variables (for example, 2·x+3, SIN(x), and SIN(y)).  

•        Implicit function plotsImplicit_Plots are made when plotting equations of the form u = v, where u and v are expressions involving at most two variables (for example, x^2+y^2=4 plots as a circle of radius 2).

•        Inequality plots are made when plotting inequalities or Boolean combinations of inequalities having at most two variables (for example, x^2+y^2<4 plots as a filled circle of radius 2.

•        Data point plotsYI._GS are made when plotting data points of the form [a, b] where a and b are constants, or a vector of such points (for example,

[1, 1; 1, -1; -1, -1; -1, 1]

plots as four points).

•        Parametric plotsParametric_Plots are made when plotting two-element vectors of the form [u, v] where u and v are univariate expressions dependent on the same variable (for example, in rectangular coordinates [SIN(t),COS(t)] plots as a circle of radius 1 if t varies from −π to π.


Plots can be made using either rectangular or polar coordinates.  In rectangular coordinates, the variable x is always interpreted as the horizontal coordinate value and y as the vertical coordinate value.  In polar coordinates, the variable r is always interpreted as the radial distance from the origin and θ as the angle from the positive x-axis (for details, see the Set > Coordinate System command162L784).


More than one expression can be plotted at a time by making a vector of the expressions (see Multiple PlotsMultiple_Plots).  However a two element vector will be plotted as a single parametric expression, rather than two separate expressions.


If the 2D-plot window Insert > Plot command results in the warning message

Too many variables for this plot window!

the highlighted expression has 2 or more independent variables and cannot be plotted.  If the command results in the message

Sorry, the highlighted expression cannot be plotted

the highlighted expression was not one of the above forms, and cannot be plotted in its present form.


Derive may be unable to plot some complicated expressions directly.  However, if u is an expression dependent on the variable x that involves a function that cannot be directly plotted, plotting an expression of the form

TABLE(u, x, min, max, step)

produces a plot of u from x=min to max in steps of size step, provided the Options > Approximate Before Plotting commandEVZ132 is turned on.  Reduce the step size if some important features are missed.


Other 2D-plot Window Insert commands2CPNZFK 

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