! Dimension too large. in x-y plot

Question

I am trying to do a simple x-y plot. However, I have no idea what I am doing, which result in the duplicates to be no helpful for me. I was based on this tutorial. Can you help please?

\documentclass{article} 
\usepackage{pgfplots}
\pgfplotsset{compat=1.9}

\begin{document}

\begin{tikzpicture}
1.a. \draw[<->] (12225,0)  -- (0,0) --
(0,6);
1. \draw[<->] (12225,0) node[below]{$speedup$} -- (0,0) --
(0,6) node[left]{$N$};
2. \draw[very thick] (755, 1.4) --(1978, 1.6) -- (6273, 1.8) -- (12222, 2.1);
\end{tikzpicture}

\end{document}

Answer 1

1. please update your system as pgfplots 1.9 is quite old.
2. get rid of those numbers in front of \draw (I guess they are a copy paste error)
3. reduce the numbers in your coordinates. The TikZ coordinates are measured in cm by default. You can change this but why do you want to have something at point 12222? The maximum right here seems to be 575 but still, 575 cm won't fit in your article, I fear.
4. For your example you just need to load tikz.
5. $speedup$ is wrong. Leave away the dollar signs or do \textit{speedup}, if you want italics.

I would recommend to go with pgfplots:

% arara: pdflatex

\documentclass{article} 
\usepackage{pgfplots}
\pgfplotsset{compat=1.12}

\begin{document}    
\begin{tikzpicture}
    \begin{axis}[%
        ,xlabel=$N$
        ,ylabel=speedup
        ,axis x line=bottom
        ,axis y line=left
        ]
        \addplot[very thick] coordinates {(755,1.4) (1978, 1.6) (6273, 1.8) (12222, 2.1)};
    \end{axis}
\end{tikzpicture}   
\end{document}