7,240 reputation
1625
bio website
location
age
visits member for 2 years, 1 month
seen 2 hours ago

16h
comment Straighforward iteration with mathematica instead of recursion
You should show values for your constants and the way you specify them as well. This runs in very fast for me but I'm guessing about what you are doing.
16h
comment Straighforward iteration with mathematica instead of recursion
you have a bunch of unbalanced parenthesis in your code. Please check it since its not obvious how to fix.
2d
comment Kernel crashes when plotting $z=\sqrt{(x^2 + y^2)^0}$
confirmed, but so what? The workaround is "don't do that".. (Wrapping the expression in Evaluate fixes it.. )
2d
comment Import selective elements from mixed (text and numbers) data file
Just checked that, it is in fact faster to import the whole works and take what you need afterward.
2d
comment Exporting row vector as a column in excel
Note the "A" here is the sheet name not the column ( "A" might not have been the best choice for the example.. )
2d
comment Update variable with incrementing value
the first line in you loop v- .. basically does nothing. The expression is evaluated and the result discarded since you dont do anything with it.
2d
comment Double integral changing the limits
In this case you don't get a different result, but no result at all in the first case. If you pick a value for a and use NIntegrate on the outer integral for the first case you can show that you get the same answer, ie. they are equivalent, mathematica just cant do it in the one order.
2d
comment Find constants in a function?
try == 123456
2d
comment Import selective elements from mixed (text and numbers) data file
nice. does this perform any different vs Import[...][[1,All,{2,3}]]
Sep
15
comment Find arc length
You can specify PlotPoints->some big number if you are concerned about the accuracy
Sep
15
comment Find arc length
FYI ArcLength: Introduced in 2014 (10.0)
Sep
12
comment Join decimal part
similarly: ToExpression[StringJoin[Riffle[ ToString /@ #, "."]]] & /@ Partition[{0, 1, -2, 259}, 2]
Sep
12
comment Join decimal part
Sounds like you are after a kludge solution to a problem that ought to be fixed on the matlab side.
Sep
12
comment Combining more than two lists by first column as index
not really a dup but it is a straightforward modificaiton: {#[[1, 1]] , Flatten[ Rest /@ # ]} & /@ Select[GatherBy[ Join[list1, list2, list3] , #[[1]] &], Length[#] > 2 &]
Sep
12
comment ReadList or any other command to read in blocks of very large numbers
possible dup: mathematica.stackexchange.com/questions/33498/…
Sep
12
comment Plotting an orbit using first principles
Fair enough to use mathematica to learn procedural programming, but you need to show what you have tried. As is we dont know where to begin. The mathematica equivalent of Fortran do is Do ..
Sep
12
comment Problem with importing numbers resulting from an executed file in Mathematica
on further thought, if the exponent is the issue you should still get the result imported as a string. Can you clarify what you mean by " it seems like these values are not imported "
Sep
12
comment Problem with importing numbers resulting from an executed file in Mathematica
The simplest thing would be to fix your fortran so you don't loose the 'E' with the three digit exponent. Show the fortran write/format statements if you need help with that.
Sep
11
comment how to find the vector intersection in a collection of triangulated 3D points?
note this can be done in closed form: use your PointPlaneIntersection on each triangle, then the resulting 2d insideness check has an analytic formula. This probably is a tad faster than belisarius approach.
Sep
11
comment Save output of NDSolve to a file
You can grab the actual points used by Plot with Cases[plot, _Line, Infinity][[1, 1]]. BTW, not part of your question, but you should use Export instead of raw Open/Write operations.