21,218 reputation
42568
bio website none
location Ann Arbor, MI
age 77
visits member for 2 years, 2 months
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
reviewed No Action Needed Sizing elements correctly in a DistributionChart with custom ChartElementFunction
Nov
11
comment Equation is solved quickly using Solve but takes too long using NSolve
Find root works works well for this equation. FindRoot[(1. - (2.25577*^-5) h)^5.2558 == 0.9644952131579817, {h, 300}] returns {h -> 303.869} essentially instantaneously.
Nov
11
revised Equation is solved quickly using Solve but takes too long using NSolve
deleted 11 characters in body
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 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
revised Using Integrate to define a function
Routine clean-up