Ted Ersek
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 Mar17 accepted Median household income for each county in Maryland Mar17 accepted Find the volume & weight of a US$4,000,000 gold ingot Mar5 asked Median household income for each county in Maryland Mar5 asked Find the volume & weight of a US$4,000,000 gold ingot Feb8 awarded Yearling Feb7 awarded Good Question Oct19 answered Catching error in middle of evaluation of compiled function Sep23 comment A problem about fixed point iteration theory I didn't intend to say you are wrong. However, one who does not read carefully might think precision always decreases as computation continues. I wanted to make it clear that isn't always the case. Sep21 comment A problem about fixed point iteration theory From the explanation above you might conclude that the result of a computation always has less precision than the precision than the numbers used in the computation. However, you increase precision in the next two examples. ------- In[1]:= x=SetPrecision[6.2,4.0]; Precision[Erf[x]] Out[2]= 19.9801 In[3]:= Precision[2+(x-62/10-10^-30)^6] Out[3]=19.5467 Sep19 comment Ted's explanation for the 3rd argument of ListCorrelate doesn't apply to the {1, -1} case? It looks like I did understand what ListCorrelate does with the third argument, but in that example above, I didn't use the right way of rotating the kernel. I wrote that a long time ago. I have to speculate that I didn't notice that the comparison returned False. I think I should use Mr. Wizard's way of rotating the kernel. When I make that change I will credit Mr. Wizard. Sep18 comment How do I evaluate only one step of an expression? @Tangshutao, You can download the Mathematica notebook from library.wolfram.com/infocenter/MathSource/4557. It also includes a notebook of Graphics tricks, but they are quite out of date. Aug18 asked OpenCL vs. CUDA with Mathematica Aug5 accepted Problem setting up C compiler on a Mac Aug3 comment Problem setting up C compiler on a Mac I evaluated that simple example. It compiles without problem, and it works. The problem is solved. Aug3 comment Problem setting up C compiler on a Mac After doing that I see the clang file. Then I wrote the simple Compile function acl suggested below. It compiled without problem and it works. The problem is solved! Aug3 comment Problem setting up C compiler on a Mac FileNames["/usr/bin/clang"] returns {/usr/bin/clang}. I downloaded and installed Xcode, registered with Apple as an xCode developer. I can open the xCode IDE, but there may be some other steps needed to get it working. Anyway, I thought xCode is an objective-C compiler. From what I read it sounds like you can't write a C program for OSX. It seems you have to write an objective-C program instead. However, Compile in Mathematica doesn't allow for CompilationTarget->"objective C". So what do I do next? Aug3 asked Problem setting up C compiler on a Mac Jul13 comment How to make use of Associations? I have been a devoted Mathematica user since version 1.2, but I never picked up much CS education. As a result you always loose me when you talk about immutable, deep copy, shallow copy, bindings, semantics, etc. Jul13 accepted Front End Find feature broken in Version 10 with OSX Mavericks? Jul13 comment Struct equivalent in Mathematica? This comes up too often. If yo insist on using struct, program in C. If you decide to use Mathematica, read relevant portions of the documentation and you will see how the language is intended to be used. Then you should use it as Wolfram intended. You are like a Chinese person trying to use a knife and fork the same way they would use chop sticks.