% Author: Dr. Matthias Jung, DL9MJ
% Year: 2020
\begin{tikzpicture}
	\pgfplotsset{
		every axis plot/.append style={line width=0.8pt},
	}
    \begin{axis}[%
        /pgf/number format/1000 sep={ },
        /pgf/number format/use comma,        
        axis lines=middle,
        axis line style={-Triangle},
		width=\linewidth*\getDarcImageFactor,
        height=3cm,
        scale only axis,
        ytick={-1,0,1},
        every major tick/.append style={thick, black},
        xtick={0.25*pi,0.5*pi,0.75*pi,pi,1.25*pi,1.5*pi,1.75*pi,2*pi,2.5*pi},
        grid=major,
        grid style={line width=.1pt, draw=gray!10},
        major grid style={line width=.2pt,draw=gray!50},
        xticklabel=\empty,
        yticklabel=\empty,
        xtick style={draw=none},
        ytick style={draw=none},
        xmin=0,
        xmax=2.2*pi,
        ymin=-1.5,
        ymax=1.5,
        xmajorgrids=false,
        ymajorgrids=false,
        xlabel style={at={(ticklabel* cs:1)},anchor=north east},
        ylabel style={at={(ticklabel* cs:1)},anchor=south east, rotate=90},
        ylabel={Amplitud},
        xlabel={$t$},
    ]
    %\addplot[domain=0:2.0*pi,black,samples=3000] {cos(28*x*180/pi)};

    %\addplot[domain=0.0*pi:0.5*pi,black,samples=300] {cos(28*x*180/pi)};
    %\addplot[domain=0.5*pi:1.0*pi,black,samples=300] {cos(14*x*180/pi-180)};
    %\addplot[domain=1.0*pi:1.5*pi,black,samples=300] {cos(28*x*180/pi-180)};
    %\addplot[domain=1.5*pi:2.0*pi,black,samples=300] {cos(14*x*180/pi)};

    \addplot[domain=0.0*pi:0.5*pi,black,samples=300] {cos(28*x*180/pi+90)};
    \addplot[domain=0.5*pi:1.0*pi,black,samples=300] {sin(28*x*180/pi)};
    \addplot[domain=1.0*pi:1.5*pi,black,samples=300] {cos(28*x*180/pi+90)};
    \addplot[domain=1.5*pi:2.0*pi,black,samples=300] {sin(28*x*180/pi)};

    %\addplot[domain=0.0*pi:0.5*pi,black,samples=300] {cos(28*x*180/pi+90)};
    %\addplot[domain=0.5*pi:1.0*pi,black,samples=300] {-0.3*sin(28*x*180/pi)};
    %\addplot[domain=1.0*pi:1.5*pi,black,samples=300] {cos(28*x*180/pi+90)};
    %\addplot[domain=1.5*pi:2.0*pi,black,samples=300] {0.3*cos(28*x*180/pi+90)};
    
\end{axis}
\end{tikzpicture}%