MHB TikZ Challenge 1 - Geometrical Diagram - Votes

AI Thread Summary
A challenge was held to create impressive geometrical diagrams using TikZ, with voting open for two weeks. Participants submitted various diagrams showcasing different mathematical concepts, including triangles, direction fields, and trigonometric foundations. The voting concluded with 15 participants, and the results announced MarkFL as the winner, followed by Serena, lfdahl, and greg1313. The thread celebrated all contributors for their efforts and creativity in the challenge. The discussion has now been closed.

What is the best TikZ contribution for a geometrical diagram?


  • Total voters
    15
  • Poll closed .
I like Serena
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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​
 
Mathematics news on Phys.org
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.
 
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