circlestikz-pgf
I have drawn a square as shown below. However, I need to draw a quarter-circle inside the square such that the radius of the quarter-circle is 1 and it the center is drawn in the bottom left. Please keep code minimal, I am a beginner.
\coordinate[label=below:$A$] (A) at (0,0);
\coordinate[label=:$B$] (B) at (0,1);
\coordinate[label=:$C$] (C) at (1,1);
\coordinate[label=below:$D$] (D) at (1,0);
\draw[] (0,0)--(0,1)--(1,1)--(1,0)--(0,0);
I suggest that you base everything on the center of the circle in which case the calculations can easily be automated with the additional TikZ library: \usetikzlibrary{calc}
You can set the angle and radius you want via:
\newcommand*{\ArcAngle}{60}%
\newcommand*{\ArcRadius}{2.0}%
Everything else is computed based on these. You can adjust these to get the specific result you desire.
Two other tweaks that I have defined below are to adjust how far the dashed lines extend past the arc, and how far past the arc the label is placed (as percentages):
\newcommand*{\LineExtend}{1.25}%
\newcommand*{\LableExtend}{1.10}%
\documentclass{standalone}
\usepackage{tikz}
\usetikzlibrary{calc}
\newcommand*{\ArcAngle}{60}%
\newcommand*{\ArcRadius}{2.0}%
\newcommand*{\LineExtend}{1.25}%
\newcommand*{\LableExtend}{1.10}%
\begin{document}
\begin{tikzpicture}
\pgfmathsetmacro{\XValueArc}{\ArcRadius*cos(\ArcAngle)}%
\pgfmathsetmacro{\YValueArc}{\ArcRadius*sin(\ArcAngle)}%
\pgfmathsetmacro{\XValueLabel}{\ArcRadius*cos(\ArcAngle/2)}%
\pgfmathsetmacro{\YValueLabel}{\ArcRadius*sin(\ArcAngle/2)}%
\coordinate (Origin) at (0,0);
\draw [thin, dashed] (Origin) -- ($(\LineExtend*\ArcRadius,0)$);% Horizontal
% Extend this past the (\XValue,\YValue)
\draw [thin, dashed] (Origin) -- ($\LineExtend*(\XValueArc,\YValueArc)$);
\node (interaction) [circle, solid, draw, fill=lightgray]
at (Origin) {interaction};
\draw [<->] ($(Origin)+(\ArcRadius,0)$)
arc (0:\ArcAngle:\ArcRadius);
\node at ($\LableExtend*(\XValueLabel,\YValueLabel)$) {$\theta$};
\end{tikzpicture}
\end{document}
For this simple case, you can fake it
\begin{tikzpicture}
\begin{axis}[
trig format plots=rad,
axis lines = middle,
enlargelimits,
clip=false,
legend entries={Maxima,Minima}
]
\addplot[domain=-2*pi:2*pi,samples=101, black,forget plot] {sin(x)};
\addplot[domain=-3*pi/2:pi/2,samples=2,only marks,mark options=red] {sin(x)<0?NaN:sin(x)};
\addplot[domain=-pi/2:3*pi/2,samples=2,only marks,mark options=blue] {sin(x)>0?NaN:sin(x)};
\end{axis}
\end{tikzpicture}
Best Answer
You can do that with
This may or may not be self-explanatory. It draws a circular arc with radius 1 starting at the point D.
start angle=0means that it is the point on the circle at an angle of zero that is placed atD.