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hey guys, i have data points that i was given in class and when i graph it, it seems to be a polynomial function with powers less than one. my job is to create an equation for this graph. I thought i could do some curve fitting to find the equation but polyfit only works with integer order values. now since i know this function has powers that are less than 1, is there another function i could use that acts like polyfit that takes in orders less than one? the reason i repost this is because some jokester sent me a link to an irrelavant site trying to be funny 
Subject: big problem, need some help From: Richard Startz Date: 20 Nov, 2010 22:57:34 Message: 2 of 8 
On Sat, 20 Nov 2010 21:49:04 +0000 (UTC), "Greg " 
Richard Startz <richardstartz@comcast.net> wrote in message 
Subject: big problem, need some help From: Richard Startz Date: 20 Nov, 2010 23:55:00 Message: 4 of 8 
On Sat, 20 Nov 2010 23:31:03 +0000 (UTC), "Matt Fig" 
ok guys here is what i have. i looked at the data and it seems to look like a y = Cx^p where C is a constant and p < 1. By hand calculations, i found the derivative to look something like a y' = Cx^p graph where C is still a constant and p is less than 0. I then took natural log of both sides to get ln(y') = ln(C) + pln(x). When i plot ln(y') vs ln(x) i will be able to solve for my y intercept and slope, thus allowing me to solve for C and P. But when i try to fit that to the data, it has huge error which means there is another function involved with more coefficients. That's why I was wondering if there was a function in matlab that could fit a curve to my nonlinear function with powers less than one and give me the coefficients. I then could write a function that would minimize the error to it. 
My data also contains a data point at (0,0). When I try to take log(0), it is going to be undefined so that is not going to work.... 
My data has a point at (0,0) so taking log of each of those values will be undefined. So won't this not work? 
On Nov 20, 8:17 pm, "Greg " <gharringto...@gmail.com> wrote: 
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