21,056 reputation
42568
bio website none
location Ann Arbor, MI
age 77
visits member for 2 years, 1 month
seen yesterday

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.


Nov
11
revised Equation is solved quickly using Solve but takes too long using NSolve
Minor clean-up
Nov
11
revised How to download and combine S&P 500 stock prices
deleted 12 characters in body; edited title
Nov
11
reviewed No Action Needed Permute indices of a large sparse array
Nov
10
comment How to exclude some indices in defining Table?
@kguler, +1. Should have thought of that one. I suspect anything that uses Range and functions that work on packed arrays without unpacking will be fast.
Nov
7
revised How to exclude some indices in defining Table?
added 47 characters in body
Nov
7
answered How to exclude some indices in defining Table?
Nov
7
reviewed Reviewed How to exclude some indices in defining Table?
Nov
7
revised How to exclude some indices in defining Table?
deleted 10 characters in body
Nov
7
revised Distance between vectors does not match distance between probability distribution
Routine clean-up
Nov
7
reviewed Approve suggested edit on How to exclude some indices in defining Table?
Nov
6
comment solve recursive factorial function
RSolveValue[{a[n + 1] - (n + 1)*a[n] == 17160, a[10] == 10}, a[n], n] should work. Note (n + 1) rather than [n + 1].
Nov
6
reviewed Looks OK Removing all values from a list that satisfy a given condition
Nov
4
answered Built-in way to convert Integer to Ordinal String
Nov
4
revised Built-in way to convert Integer to Ordinal String
Improved formatting
Nov
4
comment How to simplify only the lowest level of a nested expression
You say that A, B, ..., J represent "expressions not containing any brackets". I am very skeptical of this claim. Remember that even basic expressions such as a + b, a b, and {a, b} are just display forms for Plus[a ,b], Times[a, b], and List[a ,b]. I think you need to show us what A, B, ..., J really are.
Nov
4
revised How to simplify only the lowest level of a nested expression
Routine clean-up
Nov
4
comment Trouble with function
You have likely been down-voted because your question does not follow our guidelines for formatting questions. Someone with more than 100 rep points should be familiar and compliant with those guidelines.
Nov
4
revised Using Integrate to define a function
Routine clean-up
Nov
4
reviewed Looks OK How can a field be efficiently added to a Dataset?
Nov
4
answered CoordinateTransformData (cartesian to spherical)