Bezier curve is really a set of curves (Linear Bezier curve, Quadratic Bezier curve, Cubic bezier curve ...). The Bezier curve in Pstricks is cubic Bezier curve. And to to determine a cubic Bezier curve four control points are needed ("How to draw a cubic Bezier curve according to four given points" can be found in Wikipedia). So the complete form of "\psbezier" is "\psbezier [parameters] {arrowtype} (x0,y0)(x1,y1)(x2,y2),(x2,y3)".

"\parabola [parameters] {arrowtype} (x0,y0)(x1,y1)" draws a parabola with maximum or minimum (x1,y1) staring from (x0,y0).

"\pscurve [parameters] {arrowtype} (x1,y1)...(xn,yn)" interpolates an open curve through the given points. "\psecurve" is similar to "\pscurve" except that the curve is not extend to the first and last points. "\psccurve" draws a closed curve.

The curvature of a curve is controlled by the parameter "curvature".

Now we use these commands to draw several curves.

\documentclass{article} \usepackage{pstricks} \begin{document} \begin{pspicture}(5,5) \psset{showpoints=true} \psbezier[linecolor=green] (0,0)(0,3)(5,1)(5,5) \parabola[arrowsize=10pt] {->}(5,5)(2.5,0) \pscurve[linecolor=red] (0,4)(1.25,5)(2.5,4)(3.75,3)(5,4) \pscurve[linecolor=blue, curvature=0.5 0.1 0] (0,1)(1.25,0)(2.5,1)(3.75,2)(5,1) \psccurve[fillstyle=solid, fillcolor=yellow] (3,4)(4.5,4)(4.5,4.5)(3,4.5) \end{pspicture} \end{document}

Fig.1 Draw Curves using Pstricks |

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