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Hi, I have looked at your attachment. One of the equations you wish to solve has the form {-(1/f[z]^3) + 2.03742*10^7/((1/3 - 0.166597 (1 + 8.14968/f[z]^2)^3.)^2 (1 + 8.14968/f[z]^2) f[z]^3) + (f^\[Prime]\[Prime])[z]}...
My purpose here is to show a curious (to me at least) result that followed from browsing through the wealth of astronomical data that is available to anyone who has access to Mathematica. The naked eye stars seem like a good place for a beginner...
Today is Pi day, and indeed a typical way to impress people with the power of Mathematica is to display Pi to an obscene number of decimal places. It is the purpose of this note, however, to exhibit a more refined display of power in which...
Thank you for your response. Your suggestions have improved the performance of the script, so that it runs roughly twice as fast. Sometimes there are wild variations in speed, and I have attached a pdf file that shows the results for 10 trials.
Yesterday (11/8/2014) I spent a fair amount of time preparing a submission, but when I hit the "Publish" button my submission evaporated and the message "Message Boards is temporarily unavailable" appeared. What is going on??
Thank you very much. I forgot my rule could mess things up deep within the expression to which it is applied.
I am not familiar with the literature on SURF, so it will take some effort to get to the bottom of this.  In the meantime, my guess is that this is definitely a "bug" and not a "feature."
I just noticed that the typography in my posting is screwed up.  It should be the following: [mcode]cases[arg_, a_] := Cases[arg, a, {0, \[Infinity]}]; ngrid[arg_] := Grid[arg, Frame -> All, Alignment -> Left]; partslist[arg_] := ...
I got good results when I added PlotRange->All to your options