Smoothing cubic spline (least squares)

Please choose:
My own (x,y) - data

Specify the number of your data points: 4<=n<=200


n =

Type here your (x,y) -data, each point on a new line, the two numbers separated by blank or comma, no parentheses

(x,y)=

Do you want to see a printed formula representation of the spline?

yes
no

Specify here a value for the allowed empirical variance:

Var =
Synthetic data

Choose a function

f(x) = x2/3
f(x) = 1/(1+25x2)
f(x) = sin(2*pi*x)
f(x) = tanh(x)
f(x) = exp(x)
a function defined by yourself:
Please type the evaluation program of your function here using FORTRAN rules. Your final statement must be
      fu= some expression you computed before or just here depending on x
You may use the constants pi, e(=exp(1)), sqrt2(=1.414...), the integer variables i,j,k, the logicals bool1,bool2,bool3 and the double precision variables sum,h1,h2,h3,h4,y(100),z(100),a(100,100) which are all intialized with zero resp. .false. . The routine has the parameters x (double, input) and fu (double out). never change x!. first is a local integer and set 0 before calling the function the first time. You may use this in order to initialize some local data and set it 1 afterwards to avoid multiple such initialization. Your settings of the local variables are preserved during program execution.

Specify the number of data points which will be generated
n =
Important: 4 <= n <= 200 !

Specify the interval from where the x-data should be taken:
a = b =

Specify the error level for generating the random errors:
Level= Important: must be in [0,1] !

Click on "evaluate", in order to submit your input.

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18.02.2015