on my question, user Javi_gg1 send me an answer that's right for me. This answer have this code
\draw[ultra thick, red] plot (\x, {sin(deg(exp(ln(\fmin)+\x/\xmax*(ln(\fmax)-ln(\fmin)))*\x))} );
I could not understand how he works. is there anyone (maybe javi_gg1) who can explain it to me? Because I would change some aspect.
\xdenoting the parameter, the x-coordinate being equal to\xand y beingsin(deg(exp(ln(\fmin)+\x/\xmax*(ln(\fmax)-ln(\fmin)))*\x)). Without a referral to the post, one cannot tell what the domain and are because they were either set outside the plot or the default values, nor what\fmaxand\fminare. The answer you are referring to setsdomain=0:\xmaxandsamples=500. – Dec 13 '18 at 18:54exp(ln(\fmin)+\x/\xmax*(ln(\fmax)-ln(\fmin)))*\xcan be rewritten as\fmin*((\fmax/\fmin)^(\x/\xmax))*\x, so it multiplies\xby an exponential that equals\fminat\x=0and\fmaxat\x=\xmax. Why the author of this answer has chosen to write it in this way, is hard to say, but may not necessarily be a question that is suited for this forum. If you really want to know what this function does, plot it (without wrapping it intosin(deg(...*\x)). – Dec 13 '18 at 19:23:)– Paulo Cereda Dec 13 '18 at 20:43