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awarded  Curious
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Mar
25
accepted logplot for negative valued function
Mar
21
awarded  Teacher
Mar
21
answered logplot for negative valued function
Mar
21
revised logplot for negative valued function
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Mar
21
awarded  Informed
Mar
21
revised logplot for negative valued function
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Mar
21
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}]
Mar
21
asked logplot for negative valued function
Aug
15
awarded  Nice Question
Jul
20
comment Integration leading to logarithms and chosing branch
@Artes Thanks for the link. It might be useful also ;)
Jul
20
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!
Jul
20
accepted Integration leading to logarithms and chosing branch
Jul
20
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 :)
Jul
19
asked Integration leading to logarithms and chosing branch
Jun
29
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
Jun
28
comment Ignoring Indeterminate Results
Thanks, quite useful, I think this will definitely solve my problem!
Jun
28
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!
Jun
28
revised Ignoring Indeterminate Results
added 2 characters in body