fitting a curve and adding values

hi all,

suppose i have the follo wing(i know it's linear but just for example of code)

x = [ 1 2 3 4 5];
i want to fit a spline through x and then use that to obtain twice as many values so that i would end up with 10 values in vector x. is that possible and how would that have impact on the data?

thank you!!

Answer 1

[Azzi Abdelmalek]

%you hav to specify x coordinate and y coordinate

 x= [ 1 4  5   8 10];  y=sin(x) %for example
 f=fit(x', y','smoothingspline')
 %if 
 new_x=[1 2 3 4 5 6 7 8 9] %for example
 new_y=f(new_x')

[Matlabbey]

but what if i only have data values? would i just use 1,2,3,4 etc?

[Azzi Abdelmalek]

ok if you have for example

 y=rand(1,10)  % data values 
 %then you must create x values 
 x=1:length(y)
 f=fit(x', y','smoothingspline')
 %then you can interpolate for 
 x1=[1 1.5  1.3 4.5 6.7];
 y1=f(x1)