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Oct
29
comment High-Precision NSolve
Does NSolve[SetPrecision[f1[x]==f2[x], 100], x, WorkingPrecision->100] work? (On 8.0.0.0, your version gives no warning and a result of {{}}, so I can't check myself).
Oct
28
comment Is this an error/bug with Plot Command?
@ChipHurst: Both seem not to be available at Mathematica 8; however I've found them in the web documentation. CubeRoot clearly wouldn't be a replacement for realpower, covering only the very special case $x^{1/3}$. Surd (which IMHO is a contender for the most unintuitively named Mathematica function) gives the more general case $x^{1/n}$; while it would certainly be a better building block for realpower, it's however not a full replacement because it doesn't handle e.g. $x^{2/3}$ (which is the case from the question).
Oct
23
comment Can't figure out how to apply these functions repeatedly
@Guest: OK, I think now it does what you meant.
Oct
23
comment Can't figure out how to apply these functions repeatedly
Ah, OK, I misunderstood that. I'll change the code accordingly.
Oct
23
comment Is this an error/bug with Plot Command?
@Anoldmaninthesea.: In complex numbers, $x^{1/3}$ is indeed not the inverse of $x^3$. For example, $((-1)^3)^{1/3}\ne -1$. Actually, for even exponents, the same is already true in the real numbers, where $((-1)^2)^{1/2} = 1 \ne -1$. Only for positive $x$ the two functions are inverse to each other.
Oct
23
comment Is this an error/bug with Plot Command?
@Anoldmaninthesea.: Actually, it is not the representation, but the definition of the complex power. It's just easiest described in the polar representation (most probably, internally the formula $x^y=\exp(y\ln x)$ is used, together with an appropriate branch cut for $\ln x$). However see my edit for a function that does what you want (but probably has a lot of room for improvement).
Oct
18
comment C compiler options passed by Mathematica
Did you try them separately?
Oct
18
comment C compiler options passed by Mathematica
Does it work if you prefix the space in "Program Files" with a single backslash? Or maybe use "CompilerInstallation" -> "\"C:...bin\""?
Oct
18
comment Plotting on the Raspberry Pi
Yes, I noticed that. Given that it came with the RPi for free, it didn't strike me as odd. Especially since you normally can do everything also with the kernel interface, just less comfortably.
Oct
18
comment Plotting on the Raspberry Pi
Ah, thank you, I didn't notice that. After I've seen the "Wolfram" Icon, I didn't think of searching for another icon ;-) I now found the notebook interface, and there plotting indeed works fine.
Oct
16
comment How to Use Mathematica as a C/C++ compiler
Of course Mathematica can be used as C compiler. You just first have to write the Mathematica code that compiles C programs. ;-)
Oct
15
comment How to trigger UNIX command-line command from Mathematica notebook?
@DavidZ: Thank you for that information. I just checked with Run["false"] and I indeed got 256 instead of 1, providing further evidence for this hypothesis.
Oct
15
comment MathKernel: No such file or folder of this type
If it outputs 0, you obviously have permissions. Unfortunately it also means I'm out of ideas for now.
Oct
15
comment MathKernel: No such file or folder of this type
OK, so the file is not executable. This is likely the problem. Do you generally have execute permissions on your home directory?
Oct
15
comment MathKernel: No such file or folder of this type
The + after the last x indicates that there is access control beyond the standard Unix rights. What does test -x /home/*****/Mathematica/10.0/SystemFiles/Kernel/Binaries/Linux-x86-64/MathKernel; echo $? output?
Oct
15
comment MathKernel: No such file or folder of this type
Do you also get that warning if you type df in the shell? Also, what is the output of ls -l /home/*****/Mathematica/10.0/SystemFiles/Kernel/Binaries/Linux-x86-64/MathKernel?
Oct
8
comment Central binomial coefficient
However in that form it doesn't store previously calculated values; for that you need B[n_, k_] := B[n,k] = B[n-1, k] + B[n-1,k-1].
Oct
8
comment How to set products of small variables to zero
@YuriyIvanov: Strange; for me (on Mathematica 8.0.0.0) the very expression you wrote (copy/pasted directly from your comment) evaluates to 0.
Oct
6
comment Explanation for coloring of variables by code editor?
Actually, the scroll bar shows that the notebook doesn't end at Out[139], so it is not unlikely that the reason for r being blue is somewhere down. Of course it might just as well have been erased from the notebook altogether, or even have been executed in another notebook (without using the option of having separate contexts).
Oct
6
comment A question about expanding complex functions of real arguments
You can get rid of the Re and Im by using the option TargetFunctions->{Conjugate}. But that still gives Sin and Cos for the exponential functions.