On Wed, Dec 17, 2003 at 07:47:22AM -0700, Paul E Condon wrote: > On Wed, Dec 17, 2003 at 01:57:22PM +0100, David Fokkema wrote: > > Hi group, > > > > I was not entirely sure what to put in the subject line... > > > > I did a very simple physics experiment involving two strings, two > > weights and one pulley. I'll spare you the details, but by varying one > > of the two masses, I measured the angle one of the strings made with the > > vertical. I got these results: > > > > # m2 alpha > > 0 0 > > 10 12 > > 20 23 > > 30 32 > > 15 18 > > 25 27 > > 12 14 > > 22 24 > > 27 29 > > 17 20 > > > > where the first column is the mass of the second weight and alpha is the > > angle, in which I made an error of ±1 degree. So far, so good. > > > > Now, I want to plot in gnuplot the following: m2 along the x-axis, but > > the tangent of alpha with errorbars along the y-axis. So, I have to > > process this data somewhat further to obtain a second data file with > > three columns: m2, tan alpha-low, tan alpha-high. > > > > Of course, I could use gnumeric or something like that, but I'm > > wondering if there are command-line tools out there that could do the > > job. Or should I use a scripting language? perl? awk? bc? Efficiency is > > not the problem here, ease of use is. > > > > The command-line tool to use is awk. e.g. > > awk ' {print $1, $2-D, $2+D;} ' infile >outfile > > where D is the deviation in alpha. D can be computed by a subroutine > function, but I don't have enough info to write plausible example code.
Thanks! I'll use awk. David -- Hi! I'm a .signature virus. Copy me into your ~/.signature to help me spread! -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]