shell script + gnuplot

I have to analyze about 70 PFG-NMR data (maybe more..), it’s not fun when deal with each data point routinely. Here is the goal I have and the solution I did.

Goal: using shell script (awk, UNIX tools and sed) to do simple calculation; then use gnuplot to generate a lots of plots.

Solution:

1. use shell script to format correct files that gnuplot can take as inputs
2. run gnuplot by calling run.gnu (a gnuplot script)
3. look at the PNG file generated by gnuplot

Result: see the figure here:

content of shell script:
————————–
#!/bin/sh

rm -f fit.log
for INP in *k.dat
do
newname=`basename $INP .dat`
paste gzlvl6.dat $INP > _temp1
cat _temp1 |awk ‘{printf \
“%4.3f%10.3f%10.3f%12.3f\n”,($1*0.00235)^2,log($5/100),$1,$5 }’ >_temp2
## make a proper script to generate gnuplot with good title
cp run.gnu _temp.gnu
echo “plot f(x) with lines ls 1 title ‘fitting line’, ‘”_temp2″‘ using 1:2 title ‘dioxane $newname’ with points 6″ >> _temp.gnu
/usr/bin/gnuplot _temp.gnu
## post-filename-modification
mv fit.log $newname-fit.log
mv test.png $newname.png
cat _temp2 |sort -n > $newname-all-info.txt
rm _temp*
done
—————————-

Content of run.gnu:
set terminal png
set output “test.png”
f(x)=a*x+b
fit f(x) “_temp2″ using 1:2 via a,b
set xlabel “G^2″
set ylabel “ln(I/I0)”
set yrange [-4:0]
set style line 1 lt 1 lw 3