diagramstikz-pgf
I'd like to be able to draw lines in LaTeX by specifying an angle, rather than specifying it like so
\put(0,0){\line(2,1){3}}
Is this possible? I've looked at tikz and tikz-euclid. I've even tried installing tikz-euclid, but I couldn't even do that (I found these but couldn't find the .ins for tikz-euclid). And I'm not sure if that's what I want anyway.
What do I need to do to accomplish this?
With pstricks, quite easily:
\documentclass[a4paper]{article}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\pagestyle{empty}
\usepackage[pdf, svgnames]{pstricks}%
\usepackage{pstricks-add}
\begin{document}
\begin{pspicture}
\psaxes{->}(0,0)(-6,-5)(7,5)
\psclip{
\psellipse[linewidth = 1.5pt, linecolor = Purple](1,-1)(4,3)}
\psset{linestyle = dashed, linewidth = 0.6pt}
\psline(1,-5)(1,7)\psline(-6,-1)(7,-1)
\endpsclip
\psEllipseTangents(1,-1)(4,3)(-2,3)
\psline{*-*}(-2,3)(EllipseT1)
\psline{*-*}(-2,3)(EllipseT2)
\end{pspicture}
\end{document}
Explanation: \psellipse has the coordinates of its centre for first argument. The second argument gives its horizontal and its vertical semi-axes. To have ans ellipse with other axes, you have to rotate it around its centre.
As for the psEllipseTangent macro, it allows to draw the tangent lines to an ellipse from a given point; it has the coordinates of this point as a third argument. The points of contact with the ellipse are nodes named EllipseT1 and EllipseT2.
This can give you a starting point:
\documentclass[border=4pt]{standalone}
\usepackage[utf8]{inputenc}
\usepackage{array}
\usepackage{tikz}
\usetikzlibrary{
shapes.multipart,
matrix,
positioning,
shapes.callouts,
shapes.arrows,
calc}
\definecolor{myyellow}{RGB}{245,177,0}
\definecolor{mysalmon}{RGB}{255,145,73}
\begin{document}
{
\sffamily
\begin{tikzpicture}[
thick,
myrect/.style={
draw,
fill=myyellow,
rectangle split,
rectangle split parts=#1,
rectangle split part align=left
},
myrect2/.style={
draw,
fill=myyellow,
rectangle split,
rectangle split draw splits=false,
rectangle split part align=left
},
mycallout/.style={
shape=rectangle callout,
rounded corners,
fill=mysalmon,
callout absolute pointer={#1},
callout pointer width=1cm
}
]
\node[myrect=6]
(citiesa)
{
\strut Mannheim
\nodepart{two}\strut Köln
\nodepart{three}\strut Dresden
\nodepart{four}\strut Köln
\nodepart{five}\strut Mannheim
\nodepart{six}\strut Mannheim
};
\node[myrect2,right=2cm of citiesa,anchor=south west]
(cities1)
{%
0\quad Dresden
\nodepart{two}1\quad Köln
\nodepart{three}2\quad Mannheim
\nodepart{four}3\quad Berlin
};
\matrix[
matrix of nodes,
right=2.5cm of cities1,
nodes={
draw,
fill=myyellow,
minimum height=4ex,
text width=1em,
align=center
}
]
(mat)
{
2 \\
1 & 3 \\
0 & 4 & 5 \\
};
\foreach \Fila [count=\Filai from 0] in {1,2,3}
\node[anchor=east] at (mat-\Fila-1.west) {\Filai};
\begin{scope}[line width=2pt,red]
\draw
([shift={(-5pt,1pt)}]cities1.three split west)
rectangle
([shift={(5pt,-2pt)}]cities1.south east);
\draw[->]
([shift={(20pt,1pt)}]cities1.two split east) --
++(0,-45pt);
\draw
([shift={(-15pt,1pt)}]mat-3-1.north west)
rectangle
([shift={(5pt,-2pt)}]mat-3-3.south east);
\end{scope}
\node[myrect=6,below=5cm of citiesa]
(citiesb)
{
\strut Mannheim
\nodepart{two}\strut Köln
\nodepart{three}\strut Berlin
\nodepart{four}\strut Berlin
\nodepart{five}\strut Mannheim
\nodepart{six}\strut Dresden
};
\node[myrect=6,right=4cm of citiesb,text width=1em,align=center]
(numbers)
{
\strut 2
\nodepart{two}\strut 1
\nodepart{three}\strut 3
\nodepart{four}\strut 3
\nodepart{five}\strut 2
\nodepart{six}\strut 0
};
\foreach \Valor [count=\Valori from 0] in {text ,two ,three ,four ,five ,six }
\node[anchor=east] at (numbers.\Valor west) {\Valori};
\node[rotate=90]
at ([xshift=-30pt]numbers.three split)
{some text here};
\node[myrect2,right=of numbers,anchor=south west]
(cities2)
{%
0\quad Dresden
\nodepart{two}1\quad Köln
\nodepart{three}2\quad Mannheim
\nodepart{four}3\quad Berlin
};
\node[single arrow,fill=myyellow]
at ( $ (citiesb.three split)!0.5!(numbers.three split) $ )
{\rule{1.5cm}{0pt}};
\draw[->]
(numbers.four east) -- (cities2);
\node[mycallout={([yshift=5pt]numbers.mid)},text width=5cm]
at ([shift={(-1cm,3cm)}]numbers.north west)
{\textbf{Index vector}\\ and some more text inside this callout just for the example
};
\node[mycallout={(cities2.north)},text width=4cm]
at ([shift={(2cm,3cm)}]cities2.north)
{\textbf{Dictionary}\\ and some more text inside this callout just for the example
};
\end{tikzpicture}
}
\end{document}
The result:
TikZ was used to produce this example.
The main shapes used were rectangle split (from the shapes.multipart library), rectangle callout (from the shapes.callouts library) and matrix of nodes (from the matrix library).
Styles were used to simplify the code; positioning of the elements was achieved using the positioning and calc libraries.
Best Answer
You can read about it in the pgf manual, Section 13: Specifying Coordinates.
An example:
You can also use the relative coordinates: