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 Jan17 awarded Popular Question Jul2 awarded Curious Apr23 awarded Popular Question Mar25 accepted logplot for negative valued function Mar21 awarded Teacher Mar21 answered logplot for negative valued function Mar21 revised logplot for negative valued function deleted 345 characters in body Mar21 awarded Informed Mar21 revised logplot for negative valued function added 347 characters in body Mar21 comment logplot for negative valued function Not, exactly, but I see the solution, because this does the work myTicks = N[Table[{10^-i, -10^i}, {i, -9, 1}]]; LogPlot[- f[x], {x, 0, 100}, Frame -> True, PlotRange -> {10^-9, 10}] LogPlot[-f[x]^-1, {x, 0, 100}, Frame -> True, PlotRange -> {1/10, 10^9}, FrameTicks -> {Automatic, myTicks, None, None}] Mar21 asked logplot for negative valued function Aug15 awarded Nice Question Jul20 comment Integration leading to logarithms and chosing branch @Artes Thanks for the link. It might be useful also ;) Jul20 comment Integration leading to logarithms and chosing branch This works awesome for me! Just what I was looking for. The problem is I had to evaluate in the intercal {t,0,Infinity}, but the divergence at 0 is cancelled from an additional part Log[0]. Now I can do the job with Limit[Evaluate[Integrate[(((1 + b*t)^2) t)^(-1), {t, Infinity, τ}, Assumptions -> b > 0 && τ > 1]]+Log[τ],τ->0] which yields the desired result which you can calculate by hand to be -1+Log[1/b] Now is easier, but I wanted to fix it since the function to be integrated will be more complicated later. Thanks a lot! Jul20 accepted Integration leading to logarithms and chosing branch Jul20 comment Integration leading to logarithms and chosing branch Thanks for all the clarifications. I was just pieced off by the point that, if I would evaluate my result say, in the interval (2,10) I would get an imaginary part, while this would make no-sense for a definite integral. I was just wondering whether I could tell Mathematica some assumption so it would choose the desired sign in my case. Nevertheless, the solution below works perfecto for me :) Jul19 asked Integration leading to logarithms and chosing branch Jun29 comment Ignoring Indeterminate Results Ok, sorry. Finally the problem was solved using Table instead of Array, which keeps the problematic results in the vector. An alternative is not to add the ; at the end, so the output with error is produced and can be further used. However, the problematic parts must be removed by hand, since they are not labelled by Indeterminate rather than NIntegrate[...]. However, being rare such cases they don't represent a huge problem Jun28 comment Ignoring Indeterminate Results Thanks, quite useful, I think this will definitely solve my problem! Jun28 comment Ignoring Indeterminate Results Thanks, I could solve my problem. The point is that (as I have changed above) I was saving my information in the Integrals variable, which information was lost in case there was some overflow. I didn't see the output due to the ;. However, this is what I would expect: all the numbers calculated plus some overflow where errors occurred. However, when using Table, this is no longer a problem, then Integrals keeps all the numbers and the overflow, which I can remove by hand to further use this variable through the program. Thansk a lot!