20,776 reputation
42568
bio website none
location Ann Arbor, MI
age 76
visits member for 2 years
seen 10 hours ago

I am a retired software developer. I retired at the end of 2003 and since then my computer programming activities have been for recreational purposes. I find Mathematica excellent for that.

I started using Mathematica in 1997 (Ver. 3). I am currently using Ver. 9. Although I have used Mathematica for all kinds of stuff, I use it mostly to pursue my long standing interest in Euclidean geometry, both in its classical Greek synthetic form and in its more modern analytical/transformational form.


11h
comment Parametric Plot 3D won't show up
The form of the 1st argument is wrong for ParametricPlot3D. It should have the form {fx, fy, fz}, not {implicit-equation, fy}
1d
comment How to use a C compiler without having SystemModeler
I have no knowledge of the Windows platform. I make no recommendation.
1d
comment How to use a C compiler without having SystemModeler
Yes, you must have a C compiler install on your system to use it.
1d
comment How to use a C compiler without having SystemModeler
You do not need SystemModeler to compile code in Mathematica.
1d
comment How to fix the order in which text appears in an axis label (V7)
As nobody has mentioned the elephant in the room, I will. You have expressed your label text as a multiplication and Mathematica is doing its normal lexical reordering on it.
2d
comment Need help with GRE study question
The answer is 1250, which comes from solving n/10 + (1 - 25/100 - 20/100) 9 n/10 + 245 n/1000 + 200 == n
2d
comment Equation of a transformed ellipsoid
I am having trouble with trying to understand what you are asking. 1) you use left-handed coordinate system in your diagram. This in not consistent with Mathematica's way of plotting with a right-handed coordinate system. 2) You ask about doing a rotation about the y-axis, but your diagram shows a translation along the x-axis. 3) you introduce a parameter h in you volume expression without explanation or defintion.
Oct
18
comment Rationalize complex numbers
Seeing as 4/3 + I N[ Sqrt[2]/3] is immediately and automatically converted to 1.33333 + 0.471405 I, I don't see how it can be done.
Oct
18
comment How to tell Eigensystem the type of the elements comprising a matrix I would like to diagonalize
Your gravatar is a near-twin of mine. I am surprised I never noticed this before since you have been participating in Mathematica.SE for well over a year. However, I only noticed now when I saw my gravatar next to yours after editing this question.
Oct
18
comment Include Formatting Save As .nb to .m
I can not speak for WRI as to why they chose to implement their code editor the way they did, but .nb files have never stored indentation information for input cells.
Oct
18
comment create a function that converts a character string consisting of lowercase letters of the english alphabet to a number
The English alphabet has 26 letters, so how does z end up getting assigned 27?
Oct
18
comment Getting a blank plot when plotting two functions with Plot3D
@Nasser. I think L is supposed to l, which has value 3.
Oct
17
comment What is the best way to flatten a linked list with lists as values?
+1 Your answer is very enlightening. The test I referred to in my comment to the question only looked at ways of flattening the usual linked lists. Flatten and Partition are still good for that. I didn't think to use a bag because I didn't know that bags existed in Mathematica. I would have happily used your AngleBracket idea had I been clever enough to think of it.
Oct
17
comment Request for clarification of Eigensystem::eivn message
You have asked and answered enough questions on this site that you should be aware of the norms for formatting posts that are expected here. Please do a better job of formatting your posts in the future.
Oct
17
comment What is the best way to flatten a linked list with lists as values?
@Algohi. Flattening a linked list of pairs or triples comes up all the time in code involving 2D and 3D geometry. Flattening and re-partitioning is the best way I know to handle this common problem.
Oct
17
comment What is the best way to flatten a linked list with lists as values?
In test I made a couple years ago, your 'cheat' was the fastest method I found. I recommend sticking with it.
Oct
17
comment Package Problem
The 1st right-bracket in Module[{data = data0}], ... ] is a problem. It should be removed. Further, it would be a good idea to localize var and eigen by writing Module[{data = data0, var, eigen}, ... ].
Oct
16
comment Transforming recursion formulas into a functional form
Why is a recursive formula not a functional form?
Oct
16
comment Providing wrong answer on integral $\int_{-\frac{2}{3}}^{\frac{2}{3}} \left(\text{Ln}\left(\cos ^4(x)\right)+1\right) \, dx$
possible duplicate of Why does this integral have a complex component?
Oct
15
comment Transform Dataset so it can be used as training set for Classify
And what is the source of the iris dataset? It's not available from ExampleData["Dataset"].