\pgfplotsset{width=7cm,compat=1.3}

\begin{tikzpicture}
    \pgfplotsset{
        scale only axis,
        ymin=0, ymax=26000,
        scaled y ticks=false,
    }
    
    \begin{axis}[
        xmin=0, xmax=1,
        axis x line*=bottom,
        % xlabel=x-axis,
        ylabel=Number of simulations,
    ]

        \addplot[mark=x,red] table[x=Coverage certainty, y=Simulations, col sep=semicolon] {results/sim_scaling_dims_coverage_certainty.csv}; \label{scaling-plot-cov-cert}

        \addplot[mark=o,green] table[x=Hit probability, y=Simulations, col sep=semicolon] {results/sim_scaling_dims_hit_prob.csv}; \label{scaling-plot-hit-prob}

        \addplot[mark=x,blue] table[x=Victim coverage, y=Simulations, col sep=semicolon] {results/sim_scaling_dims_victim_coverage.csv}; \label{scaling-plot-vic-cov}

    \end{axis}

    \begin{axis}[
      axis x line*=top,
      axis y line=none,
      xmin=0, xmax=4,
    %   xlabel=x-axis 2
    ]

        \addlegendimage{/pgfplots/refstyle=scaling-plot-cov-cert}\addlegendentry{Coverage certainty}
        \addlegendimage{/pgfplots/refstyle=scaling-plot-hit-prob}\addlegendentry{Hit probability}
        \addlegendimage{/pgfplots/refstyle=scaling-plot-vic-cov}\addlegendentry{Victim coverage}

        \addplot[smooth,mark=*,brown] table[x=Modes, y=Simulations, col sep=semicolon] {results/sim_scaling_dims_modes.csv};
        \addlegendentry{Failure modes}
    \end{axis}

\end{tikzpicture}