MHB TikZ Challenge 1 - Geometrical Diagram - Votes

[I like Serena]

Hey all,

2 weeks ago I created a challenge to create a geometrical diagram, like a triangle, that is somehow interesting or impressive.
Now the moment of truth is here. Please everyone, give your vote!
Voting will close in 2 weeks time.

Let me recap the submissions.I like Serena

\begin{tikzpicture}[blue]
\coordinate (A) at (0,0);
\coordinate (B) at (4,0);
\coordinate (C) at (4,3);
\draw[blue, ultra thick] (A) -- (B) -- (C) -- cycle;
\path (A) node[below left] {A} -- (B) node[below right] {B} -- (C) node[above] {C};
\path (A) -- node[below] {c} (B) -- node

{a} (C) -- node[above left] {b} (A);
\path (A) node[above right, xshift=12] {$\alpha$};
\draw[thick] (B) rectangle +(-0.4,0.4);
\draw[thick] (A) +(1,0) arc (0:atan(3/4):1);
\end{tikzpicture}
[latexs]
\begin{tikzpicture}[blue]
\coordinate (A) at (0,0);
\coordinate (B) at (4,0);
\coordinate (C) at (4,3);
\draw[blue, ultra thick] (A) -- (B) -- (C) -- cycle;
\path (A) node[below left] {A} -- (B) node[below right] {B} -- (C) node[above] {C};
\path (A) -- node[below] {c} (B) -- node

{a} (C) -- node[above left] {b} (A);
\path (A) node[above right, xshift=12] {$\alpha$};
\draw[thick] (B) rectangle +(-0.4,0.4);
\draw[thick] (A) +(1,0) arc (0:atan(3/4):1);
\end{tikzpicture}
[/latexs]
This picture is special because it's a basic shape that showcases:

1. Naming coordinates.
2. Drawing a closed polygon.
3. Embellishing with properties (for color and thickness).
4. Adding labels next to nodes and next to lines.
5. Specifying relative coordinates.
6. Drawing an arc.
7. Using a mathematical function (for the angle of the arc).

greg1313

\begin{tikzpicture}[scale=2]
\usetikzlibrary{calc}
\coordinate (A) at (0,0);
\coordinate (B) at (1,2.5);
\coordinate (C) at (4,0);
\draw (A) -- (B) -- (C) -- cycle;
\draw (B) -- ($(A)!(B)!(C)$) ++(90:0.2) -- ++(0:0.2) -- +(-90:0.2);
\draw (A) -- ($(B)!(A)!(C)$) ++(-39.806:0.2) -- ++(50.194:-0.2) -- +(-39.806:-0.2);
\draw (C) -- ($(A)!(C)!(B)$) ++(68.2:-0.2) -- ++(-21.8:0.2) -- +(68.2:0.2);
\draw (A) node

{$A$} -- (B) node[above]{$B$}node[midway,above]{$c\quad$} -- (C)node

{$C$}node[midway,above]{$\quad a$} -- (A)node[midway,below]{$b$};
\node[align=center,font=\bfseries, yshift=2em] (title)
at (current bounding box.north)
{An illustration of the altitudes of a triangle, \\ intersecting at a single point called the orthocenter};
\end{tikzpicture}
[latexs]
\begin{tikzpicture}[scale=2]
\usetikzlibrary{calc}
\coordinate (A) at (0,0);
\coordinate (B) at (1,2.5);
\coordinate (C) at (4,0);
\draw (A) -- (B) -- (C) -- cycle;
\draw (B) -- ($(A)!(B)!(C)$) ++(90:0.2) -- ++(0:0.2) -- +(-90:0.2);
\draw (A) -- ($(B)!(A)!(C)$) ++(-39.806:0.2) -- ++(50.194:-0.2) -- +(-39.806:-0.2);
\draw (C) -- ($(A)!(C)!(B)$) ++(68.2:-0.2) -- ++(-21.8:0.2) -- +(68.2:0.2);
\draw (A) node

{$A$} -- (B) node[above]{$B$}node[midway,above]{$c\quad$} -- (C)node

{$C$}node[midway,above]{$\quad a$} -- (A)node[midway,below]{$b$};
\node[align=center,font=\bfseries, yshift=2em] (title)
at (current bounding box.north)
{An illustration of the altitudes of a triangle, \\ intersecting at a single point called the orthocenter};
\end{tikzpicture}
[/latexs]
This TikZ diagram includes a title.MarkFL

\begin{tikzpicture}
\draw[<->][red] (-5.5,0) -- (5.5,0) node

{$x$};
\draw[<->][red] (0,-5.5) -- (0,5.5) node[above] {$y$};
\foreach \x in {-5,-4.5,...,-0.5,0.5,1,...,5}
{
\foreach \y in {-5,-4.5,...,-0.5,0.5,1,...,5}
{
\def \angle {atan((3*\x*\y)/(2*(\x)^2-(\y)^2))};
\draw[thick,blue] ({\x + 0.1*cos(\angle)},{\y + 0.1*sin(\angle)}) -- ({\x + 0.1*cos(\angle + 180)},{\y + 0.1*sin(\angle + 180)});
}
}
\end{tikzpicture}
[latexs]
\begin{tikzpicture}
\draw[<->][red] (-5.5,0) -- (5.5,0) node

{$x$};
\draw[<->][red] (0,-5.5) -- (0,5.5) node[above] {$y$};
\foreach \x in {-5,-4.5,...,-0.5,0.5,1,...,5}
{
\foreach \y in {-5,-4.5,...,-0.5,0.5,1,...,5}
{
\def \angle {atan((3*\x*\y)/(2*(\x)^2-(\y)^2))};
\draw[thick,blue] ({\x + 0.1*cos(\angle)},{\y + 0.1*sin(\angle)}) -- ({\x + 0.1*cos(\angle + 180)},{\y + 0.1*sin(\angle + 180)});
}
}
\end{tikzpicture}
[/latexs]
This TikZ diagram illustrates a direction field for a magnetic dipole, and utilizes the following:

• Nodes for the axis labels.
• Nested foreach loops.
• The definition of an angle (slope) based on coordinates.
• Parametric values for the endpoints of line segments.

lfdahl

[TIKZ][scale=3]
\draw[step=.5cm, gray, very thin] (-1.2,-1.2) grid (1.2,1.2);
\filldraw[fill=green!20,draw=green!50!black] (0,0) -- (3mm,0mm) arc (0:30:3mm) -- cycle;
\draw[->] (-1.25,0) -- (1.25,0) coordinate (x axis);
\draw[->] (0,-1.25) -- (0,1.25) coordinate (y axis);
\draw (0,0) circle (1cm);
\draw[very thick,red] (30:1cm) -- node[left,fill=white] {$\sin \alpha$} (30:1cm |- x axis);
\draw[very thick,blue] (30:1cm |- x axis) -- node[below=2pt,fill=white] {$\cos \alpha$} (0,0);
\draw (0,0) -- (30:1cm);
\foreach \x/\xtext in {-1, -0.5/-\frac{1}{2}, 1}
\draw (\x cm,1pt) -- (\x cm,-1pt) node[anchor=north,fill=white] {$\xtext$};
\foreach \y/\ytext in {-1, -0.5/-\frac{1}{2}, 0.5/\frac{1}{2}, 1}
\draw (1pt,\y cm) -- (-1pt,\y cm) node[anchor=east,fill=white] {$\ytext$};
[/TIKZ]
[latexs]
[TIKZ][scale=3]
\draw[step=.5cm, gray, very thin] (-1.2,-1.2) grid (1.2,1.2);
\filldraw[fill=green!20,draw=green!50!black] (0,0) -- (3mm,0mm) arc (0:30:3mm) -- cycle;
\draw[->] (-1.25,0) -- (1.25,0) coordinate (x axis);
\draw[->] (0,-1.25) -- (0,1.25) coordinate (y axis);
\draw (0,0) circle (1cm);
\draw[very thick,red] (30:1cm) -- node[left,fill=white] {$\sin \alpha$} (30:1cm |- x axis);
\draw[very thick,blue] (30:1cm |- x axis) -- node[below=2pt,fill=white] {$\cos \alpha$} (0,0);
\draw (0,0) -- (30:1cm);
\foreach \x/\xtext in {-1, -0.5/-\frac{1}{2}, 1}
\draw (\x cm,1pt) -- (\x cm,-1pt) node[anchor=north,fill=white] {$\xtext$};
\foreach \y/\ytext in {-1, -0.5/-\frac{1}{2}, 0.5/\frac{1}{2}, 1}
\draw (1pt,\y cm) -- (-1pt,\y cm) node[anchor=east,fill=white] {$\ytext$};
[/TIKZ]
[/latexs]
This TikZ picture is special, because it demonstrates:
- The very foundation of trigonometry
- Construction of a coordinate system
- Construction of a grid
- Coloring of line segments
- The making of tick labels
- How to fill in with colors
- How to use different line thickness
- How to position labels​

 

[I like Serena]

Voting is over.
Thank you all for taking the time to take a look and vote. We have 15 voters!
The result:

1. MarkFL
2. I like Serena
3. lfdahl
4. greg1313

A big hurray for every one of the contributors. Thank you for your efforts!

Thread closed.