Function Of Any Line?

105 Views Asked by At

If I were to scribble a line of varying curves into a sheet of paper and for each value of X there was only a single value of Y, how can I go about finding the function for such a line in a way that is preferably practical and not overly time consuming.

1

There are 1 best solutions below

1
On BEST ANSWER

A quick and dirty solution may be to digitize the curve and then fit the data using regression. Sometimes I want to use graphical textbook data in a program. First, I take a picture of the graph in the book. Second, I upload the picture to a website that allows me to digitize the curve. My favorite such website is http://arohatgi.info/WebPlotDigitizer/app/. Third, I download the (x,y) coordinates from the website as a CSV text file. Fourth, I read the CSV data into a spreadsheet, or into another program. Fifth, I will sometimes try to fit the data to some function that is available in the spreadsheet program. The choice of function depends on the shape of the curve. Sometimes I have to use a special curve fitting program, instead of the spreadsheet. Sixth, I take the function parameters from the curve fitting program, and put them into my program.