\documentclass[11pt,letterpaper]{article}

\usepackage{filecontents}
\begin{filecontents*}{data.out}
LOGDISTANCE,distance,barnum
-1,0.100000,5.045455
0,1.000000,14.136364
1,10.000000,23.227273
2,100.000000,32.318182
3,1000.000000,41.409091
4,10000.000000,50.500000
\end{filecontents*}

\usepackage{datatool}

\listfiles

\begin{document}

\DTLloadrawdb{MyDBase}{data.out}

\DTLgetvalueforkey\Onekm{barnum}{MyDBase}{LOGDISTANCE}{-1} \Onekm

\DTLgetvalueforkey\Onekm{barnum}{MyDBase}{LOGDISTANCE}{0} \Onekm

\DTLgetvalueforkey\Onekm{barnum}{MyDBase}{LOGDISTANCE}{1} \Onekm

\DTLgetvalueforkey\Onekm{barnum}{MyDBase}{LOGDISTANCE}{2} \Onekm

\DTLgetvalueforkey\Onekm{barnum}{MyDBase}{LOGDISTANCE}{3} \Onekm

\end{document}
