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\section{Filament selection and analysis}  After 1.25 1.23 Myr and 2.09  Myr of self gravitating evolution, we selected by eyefour  filamentary features in one projection of the cloud, shown in figure \ref{finderimage}. This image was These images were  constructed by calculating the surface density of gas in the range $10^3 < n/{\rm cm}^{-3} < 10^{4.5}$. This is roughly the density range traced by C$^{18}$O observations; we then converted the surface density to integrated line intensities. This conversion, using equation 2 of \citet{2001ApJ...551..687M}, is only meant to give a low-order approximation to an observation. This approximate `observation' of our data yields an idea of what this simulation might look like in the motivating observations of \citet{2013A&A...554A..55H}. We At 1.23 Myr we  chose one feature which, observationally speaking, would probably be deemed an obvious filament (filament D), D1),  two that might be considered a ridge of star formation activity consisting of distinct dense sites linked by more tenuous emission (filaments A B  and C), C1),  and one region that has entered a collapse phase (filament B). A).  This is not intended to be a comprehensive study of all the filaments in this projection, but rather an exploratory look at a few of the more prominent features. At this point 24 M$_{\sun}$ of gas was in sinks, yielding an integrated star formation efficiency of $\sim 0.05\%$.  \subsection{Line-of-sight velocity structure}  The rectangles surrounding the selected filaments define a coordinate system with axes aligned along the long axis or length $L$ of the filament, and the width $W$. The depth $D$ is the same axis that the surface density is projected along. We stepped along the $L$ and $W$ coordinates with a stepsize equal to the simulation's base resolution, and calculated at each point the density-weighted line-of-sight velocity integrated along the $D$ axis, using the same density range used to calculate the surface density. We binned these spectra into histograms with bin width 0.05 km s$^{-1}$.