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Ok guys, so i have a bunch of datapoints in 3d (x,y,z)

I'm trying to calculate an equation using maple that will express z as a function of x and y.

I've been browesing around for like 2 hours now with no hope. Help?

 

Hi. It is be good to be with you after 4 years.

I want to ask about Curvefitting for Data. If I have a numerical data and i want to find a function in x and y for these data.

i have a non linear equation that depends on three variables e, theta and z.

i have done calculations to calculate e while varying theta and z. theta varied among the vector [0, Pi/4, Pi/3, Pi/2] and z was varying between 1 and 20

when plotting my data it gives the following plot where z is represented on the x-axis and each curve correspond to one theta

 

i am currently able of fitting one plot to one equation i would like to fit the data points using the nonlinearfit function and to only get one equation for all the plots. is that possible in maple or not

 

Hey, I have some data points:

 

I than entered:

X := Data[() .. (), 1];
Y := Data[() .. (), 2];
f := a+b*x^c+d*x^e;
Statistics:-NonlinearFit(f, X, Y, x);
 and when I entered Statistics:-NonlinearFit(f, X, Y, x);, It wouldn't output anything.

Hello,

 

I am new to Maple.

I have a set of spreadsheet data :(x1, y1), (x2, y2) .....(xn,yn).

And I have an equation that contains an infinite series with unkowns.

e.g.) y=  A*x + sum ( B * exp(-n^2 * (x-C)) /n^2, n=1..infinity);

Where A, B, C are unkowns, which I want to get optimized values for the spreadsheet data fitting.

 

Please let me know.

Sung Yeol

Find the function f:\mathbb{R}\to\mathbb{R} satisfying the following conditions:

f(-6)=2400,f(-4)=432,f(-3)=120,f(-2...

Hey guys

I am currently working on my final project in high school. This project is about mathematical modelling within epidemology, and i am currently working on the mathematical models based on the SIR model.

The basis models for the SIR model were pretty easy, but i cant figure out how to fit data to my models. My first idea was to use the method of Leastsquare and/or Nonlinearfit, but i cant figure out how to do this in maple.

Dear All:

 I have a curve about mosfet  Coss Vs. Vds . the detail math relationship can be found in the following picture: 

  

 Can anyone fitting this picture by simple math function.

 PS: pls don't considering piecewise function 

HI,

 

I measured some points. This points are plotted in a graph. Now I want to make a fit on this points.

I now that the fit-function has to be like this:

F = A + B1 x e^(-t/C1) + B2 x e^(-t/C2)

Problem: how can I create a fitting function like that?

 

The best thing I found is the "spline"-fit, but it doesn't work properly. It has to be one lonely function, not a summary of several functions (like spline).

Hi, I'm trying to fit an equation:

starting_salary= (intercept+SEX*B0) +B1*GPA  +B2* METRICS

(metrics,sex are  dummy variables, either 0 or 1) to see how sex coefficient affects the intercept ( how it affects starting_salary)

(later on I  want to see how metrics affects starting_salary for either sex=1 and sex =0 .. anyways I disgress) 

STARTING_SALARY :=:  

GPA:=:      

METRICS: =;  

I have a huge .txt file in it is a lot of difirent numbers. At first I am doing this:

>data:=readdata(C:/text.txt, 1, integer)

Maple reads the file.
I  have a function p(x)=e^(x^4+0.5*a*x^2+b*x)
I tried to draw a histogram and then to do something with fitting, I know that then I have to do logarithm the function then I get ln(p(x))=x^4+0.5*a*x^2+b*x, the histogram then should be up side down. The point is that...

Hello everyone.

Now, I am studying nonlinear fitting method through help file of maple. Unfortunately, I'm not getting good fit using NonliearFit. The following is my psocedure:

> restart;
> with(Statistics);
> y := 1/(3.6+2.3*x)+17.6*exp(-0.2*x);
> fy := unapply(y, x);
> for x to 10 do fy(x) end do;
14.5791527795
11.9195840297
9.75432289049
7.98631476846
6.54090333018
5.35848939402
4.39086798669

Following Christopher2222 request, I wrote the following procedures for "exact" cubic Hermite spline interpolation,

p:=proc(x0,p0,m0,x1,p1,m1,x)
local t,d;
d:=x1-x0;
t:=(x-x0)/d;
p0+(d*m0+(3*(p1-p0)-d*(2*m0+m1)+(2*(p0-p1)+d*(m0+m1))*t)*t)*t
end:

pb:=proc(x0,p0,x1,p1,m1,x)
local t,d;
d:=x1-x0;
t:=(x-x0)/d;
p0+(2*(p1-p0)-d*m1+(p0-p1+d*m1)*t)*t
end:

pe:=proc(x0,p0,m0,x1,p1,x...

If for example

L := [3, 4, 6, 7, 2, 3, 5, 4, 6, 8, 20, 4, 5, 12, 0, 5, 5, 5, 3]:

b := ListTools:-Enumerate(L):
g := plot(CurveFitting:-Spline(b, v), v = 1 .. 19):
gp:=pointplot(b):

display(g,gp)

It is a nice curve but between points at x=12 and x=13 there exists a large dip, and there are a few other smaller...

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