Nikol

35 Reputation

One Badge

6 years, 160 days

MaplePrimes Activity


These are replies submitted by Nikol

@Nikol 

the main problem is the complexity of the function f. it is considered very long for 256 by 256. It is the calculation itself that is long.
as an example
, if for example to build plot3d(f,...) then it takes about 20 seconds for 800 points.

@Carl Love 

Thanks/ I would like to use in the best scenario nonlinear case/

A*f(B*x,C*y). Scale parameter

@mmcdara 

I use the term copula in the sense of the term pattern.  A template that can be used with scale and offset options.

@mmcdara

Any procedure that gives two numbers x and y a third z is a function.  It matters what procedure it is.  It must be unambiguous.  What's inside the procedure (x, y) -> z is not important.

@mmcdara

There is 2D spectrum as histogram. 256 x 256 channels. I fit the two-dimensional spectrum with the function f(x, y) := Lowess(mas,fitorder=2,bandwidth=0.07). Now I've got a function f. Next step I try use NonlinearFit(a*f(x, y), mas2, [a],... ). Apparently the function f is considered very slowly.  And my procedure can't issue a solution, it just freeze

@Nikol 

This works well :

master := Lowess(<$ (5 .. 256)>, convert(qw(1, 52 - 45 .. 258), Vector), fitorder = 2, bandwidth = 0.2);

NonlinearFit(B*master(t/a), <($10..235)>, wer, t, initialvalues = [a=1], output = [parametervalues]):

@tomleslie 

Thanks for the reply. I'll upload the sheet later. But you're wrong. Lowes can be used in NOnLinearfit. I get a great fit in the one-dimensional case. like B*f(A*x) where f(x):=Lowess()

@vv Thanks!

Why does this happen?

@epostma 

Thank you very match

@Markiyan Hirnyk 

Is it a bug?

 

@vv 

Thank you very much

@Markiyan Hirnyk 

Maple disappoints me/

 

rsolve({f(n)=0.5*f(n-1)+0.5*f(n+1), f(0)=1, f(a)=0},f(n));

with parameter is it impossible?

 

I think it's just a defect.

it's so obvious problem

I have

rsolve({ f(n+1) = f(n)+c,f(0) = 0}, {f});

return {f(n) = c (n + 1) - c}

It's a TRUE

Page 1 of 1