I have a set data points. The base axis varies from 1:512. For x values between 40 to 55, there is no data available and the data at other points is not uniform. I have applied curve fitting using smoothing spline and then plotted it on an image with base as 1:512. So visually it fills those absent points but when i see the co-efficients of the fit, It doesn't include points where the data was not available. Is there any way to get those points? I am stuck here for several days. any help would be highly appreciated. I tried my best to explain the problem. If its not clear i can explain again.