xold
and xolder
https://charttree657.weebly.com/blog/element-hunters-english-patch. are too far from the solution. If we change them asf(x)
is defined asD
. So, we see that f(D) = c1 - 2.0 * log( D / c2 )
, so we can obtain the solution analytically as D = c2 * exp(c1/2.0) = 7.26526809959e-5
, which agrees well with the numerical solution above. To get a rough idea of where the solution is, it is useful to plot f(D)
as a function of D
, e.g. using Gnuplot.f(D)
itself (given in the Fortran code) might include some typo due to many parentheses. To avoid such issues, it is always useful to first arrange the expression for f(D)
as simplest as possible before making a program.(One TIP is to extract constant factors outside and pre-calculate them.)gfortran
for example, the compiler will complain for not getting any argument for D
https://charttree657.weebly.com/blog/korg-pa1x-pro-downloads. (the second dummy argument), because it stops with the first error.