lines(0)/// set old_style on ; /// @@prerequisite affectations  \sleftarrow{\normalfont switching to old style }
///\center{Parametric plot in  \( \R\sp{3}\)}
xbasc();t=linspace(-20*%pi,20*%pi,2000); /// \sleftarrow{\normalfont \verb+xbasc+\index{xbasc@\texttt{xbasc}} clears the current graphic window and recorded graphic statements }
param3d1(sin(t),t.*cos(t)/maxi(t),t/100) /// \sleftarrow{\normalfont a \( \R\sp{3}\) curve }\index{param3d1@\texttt{param3d1}}
 xs2ps(0,'fig1'); /// @@prerequisite affectations  xs2ps(0,'fig1'); /// \sleftarrow{\normalfont replay with a Postscript driver building a postscript file}
/// \center{Plot a surface in  \( \R\sp{3}\)}
xbasc();x=linspace(-%pi,%pi,40); y=linspace(-%pi,%pi,40);
plot3d(x,y,sinh(x')*cos(y)) ; /// \sleftarrow{\normalfont a \( \R\sp{3}\) surface }\index{plot3d@\texttt{plot3d}}
xs2ps(0,'fig2'); /// @@prerequisite affectations 
/// \center{Plot a vector field in \( \R\sp{3}\)}
xbasc()
function [xdot]=derpol(t,x); xdot=[x(2);-x(1)+(1 - x(1)**2)*x(2)];endfunction
xf= linspace(-1,1,10);yf= linspace(-1,1,10);
fchamp(derpol,0,xf,yf);  /// \sleftarrow{\normalfont an  \( \R\sp{2}\) vector field } \index{fchamp@\texttt{fchamp}}
xs2ps(0,'fig3'); /// @@prerequisite affectations 
/// \center{Plot an histogram }
xbasc(); v=rand(1,2000,'n');
histplot([-6:0.4:6],v,[1],'015',' ',[-4,0,4,0.5],[2,2,2,1]);/// \sleftarrow{\normalfont histogram } \index{histplot@\texttt{histplot}}
function [y]=f2(x); y=exp(-x.*x/2)/sqrt(2*%pi); endfunction;
x=-6:0.1:6;x=x';plot2d(x,f2(x),1);  /// \sleftarrow{\normalfont superposing a \( \R\sp{2}\) curve }
xs2ps(0,'fig4');/// @@prerequisite affectations 
/// \center{Polar plot in  \( \R\sp{2}\)}
xbasc();polarplot();xs2ps(0,'fig5');  /// \sleftarrow{\normalfont an \( \R\sp{2}\) curve in polar mode }\index{polarplot@\texttt{polarplot}}
/// \center{Plot a surface given by facets in  \( \R\sp{3}\) }
xbasc();
function [x,y,z]=f3(alp,tet) 
  r=log(1+abs(alp))
  x=cos(alp).*cos(tet);
  y=cos(alp).*sin(tet);
  z=sinh(alp);
endfunction
x=linspace(-%pi/2,%pi/2,40);y=linspace(0,2*%pi,20);
[x1,y1,z1]=eval3dp(f3,x,y); /// \sleftarrow{\normalfont building a set of facets } \index{eval3dp@\texttt{eval3dp}}
plot3d1(x1,y1,z1); /// \sleftarrow{\normalfont an  \( \R\sp{3}\) surface composed by a set of facets}
xs2ps(0,'fig6');/// @@prerequisite affectations 
/// \center{Graphic basic functions \texttt{xrects}}
xbasc();plot2d([],[],rect=[0,0,1,1],strf="012");  /// \sleftarrow{\normalfont just to fix a current scale  }
xset('clipgrf');  /// \sleftarrow{\normalfont setting a clip zone in the graphic frame }
n=20;
rects=[0.8*rand(1,n);0.8*rand(1,n);0.2*ones(1,n);0.2*ones(1,n)];
xrects(rects,rand(1,n)*20); /// \sleftarrow{\normalfont a set of rectangles }\index{xrects@\texttt{xrects}}
xs2ps(0,'fig8');/// @@prerequisite affectations 
///\center{Graphic basic functions \texttt{xpolys}}
xbasc()
a=get("current_axes");  /// \sleftarrow{\normalfont get a handle on the newly created axes}
a.axes_visible="off";  /// \sleftarrow{\normalfont  makes the axes visible}
a.data_bounds=[-2*cos(%pi/6),0;2*cos(%pi/6),3];  /// \sleftarrow{\normalfont set the boundary values for x and z }
a.box="off";
theta=[-%pi/6,%pi/2,%pi*7/6,-%pi/6];
T=[cos(theta);sin(theta)];
Ts=(1/(1+2*sin(%pi/6)))*rotate(T,%pi);
x=[T(1,:);Ts(1,:)]'; y=[T(2,:);Ts(2,:)]';
x=[x+cos(%pi/6),x-cos(%pi/6),x];y=[y+sin(%pi/6),y+sin(%pi/6),y+1+2*sin(%pi/6)];
a.thickness=8;  /// \sleftarrow{\normalfont setting line thickness }\index{xset!thickness}
xpolys(x,y);  /// \sleftarrow{\normalfont a set of polyline }\index{xpolys@\texttt{xpolys}}
xs2ps(0,'fig9');/// @@prerequisite affectations 
unix(SCI+'/bin/Blatexprs panorama fig[1-9]') /// @@prerequisite affectations  /// \sleftarrow{\normalfont calling a Unix script}
unix(SCI+'/bin/BEpsf fig1'); /// @@prerequisite affectations  /// \sleftarrow{\normalfont calling a Unix script}
unix(SCI+'/bin/BEpsf fig2'); /// @@prerequisite affectations  /// \sleftarrow{\normalfont calling a Unix script}
unix(SCI+'/bin/BEpsf fig3'); /// @@prerequisite affectations  /// \sleftarrow{\normalfont calling a Unix script}
unix(SCI+'/bin/BEpsf fig4'); /// @@prerequisite affectations  /// \sleftarrow{\normalfont calling a Unix script}
unix(SCI+'/bin/BEpsf fig5'); /// @@prerequisite affectations  /// \sleftarrow{\normalfont calling a Unix script}
unix(SCI+'/bin/BEpsf fig6'); /// @@prerequisite affectations  /// \sleftarrow{\normalfont calling a Unix script}
unix(SCI+'/bin/BEpsf fig8'); /// @@prerequisite affectations  /// \sleftarrow{\normalfont calling a Unix script}
unix(SCI+'/bin/BEpsf fig9');/// @@prerequisite affectations  /// \sleftarrow{\normalfont calling a Unix script}