3,325 reputation
1737
bio website xslittlegrass.wordpress.com
location Louisiana State University, LA
age
visits member for 2 years, 3 months
seen 5 hours ago

"I want to know how God created this world. I am not interested in this or that phenomenon. I want to know His thoughts, the rest are details." --- Albert Einstein


Aug
29
accepted Numerical error in Mathieu functions
Aug
28
accepted Why does N[Re@f] give complex result?
Aug
28
awarded  Nice Question
Aug
28
comment Why does N[Re@f] give complex result?
Did Re do its job wrong? If that's true then it's really scary for me since I used a lot of Mathematica's analytical simplification in my work. I'm wondering whether Re did it correctly but N did it wrong instead. For example N[MathieuC[MathieuCharacteristicA[-(19999999999/10000000000), -2], -2, 5], 10] give me a real number. Maybe this is another expression of this. Mathieu functions have driven me crazy :)
Aug
28
comment Why does N[Re@f] give complex result?
Maybe related stackoverflow.com/questions/7798435/…
Aug
28
asked Why does N[Re@f] give complex result?
Aug
28
comment Numerical error in Mathieu functions
OK, I start to see your point. Thanks for the help :)
Aug
28
comment Numerical error in Mathieu functions
Sorry I still don't get you. But I see you use Terms options. But if you increase upto 100 terms, you get inconsistent result again. N@Block[{$MaxExtraPrecision = 500}, NLimit[Re@ MathieuC[MathieuCharacteristicA[\[Kappa], -1], -1, 0], \[Kappa] -> 2, Direction -> 1, WorkingPrecision -> 300, Terms -> 100]] (*1.11439*)
Aug
28
comment Numerical error in Mathieu functions
NLimit "numerically finds the limiting value of expr as z approaches Subscript[z, 0]."
Aug
27
comment Numerical error in Mathieu functions
What about the disagreement to NLimit?
Aug
27
comment Numerical error in Mathieu functions
I'm not convinced it's simply the round-off error, see my updates.
Aug
27
revised Numerical error in Mathieu functions
added 1356 characters in body
Aug
27
comment Numerical error in Mathieu functions
Why does this big discontinuity happen in the Mathieu function, even we are still away from the piecewise point? You think Mathematica just got wrong?
Aug
27
revised Numerical error in Mathieu functions
added 4 characters in body
Aug
27
asked Numerical error in Mathieu functions
Aug
25
asked Is it possible to pass a “shared” integer in librarylink?
Aug
24
revised How to understand shared passing of a MTensor in LibraryLink?
added 1 character in body
Aug
24
revised Why LibraryLink function crashes at a second time?
added 50 characters in body
Aug
14
revised Version 10 cannot print properly?
edited tags
Aug
12
comment Computing and plotting a spectrogram in Mathematica
What does the offset mean? Does it mean the step size of the moving window? For example, if I have a list of 8 numbers and the bin size is 4, offset=2 means every time I advance the 4-number wide window, 2 numbers ahead. Is my understanding correct? Thanks :)