Code:

`x2 = 2*c**2/(2*x**2-c**2)`

Code:

`c=3.1`

Code:

```
set xlabel "Quantity lower"
set xtics nomirror
set x2label "Quantity Upper"
set x2tics nomirror
set link x2 via 2*(3.1)**2/(2*x**2-(3.1)**2) inverse sqrt((3.1)**2*(2+x)/2/x)
#set link x via 1239.8/x inverse 1239.8/x
set ylabel "Quantity y"
set ytics 0.2
set samples 400
Spectrum(x) = exp(-(x-500)**2/(400))
set xrange[30:2000]
set format x2 "%.2f"
plot Spectrum(x) w l title "Spectrum"
```

Code:

```
set logscale x
set format x "10^{%L}"
```

I'd like to print out values on the upper axis for two values of x=100, 1000 say. Not sure if this is the right place for this but thanks for any comments!