Grdcontour with exponentially varying cont_int?

Hi, I’m wondering if there’s a way to create a contour plot where the cont_int varies exponentially? I’m thinking one has to first create an exponentially varying contour series and then use -C flag in grdcontour? If so, how would you create the exponential contour series? gmt math? not sure.

My workaround was to create a file with exponential contours with a shell macro to be used with teh -C flag:

cont=$min_cont
echo "$cont C" > cont.txt
echo "$cont"

while [ $(echo "$cont <= $max_cont" | bc) -eq 1 ]
do
cont=`awk -v a=$cont -v b=$cont_decay 'BEGIN{ print a + b*exp(a) }'`
fmt_cont=`echo $cont | awk '{ printf("%.3f\n",$1) }'`
echo "$fmt_cont"
echo "$fmt_cont C" >> cont.txt
done