Re: Forcing a Fit through a Data Point (Mathematica 5)
- To: mathgroup at smc.vnet.net
- Subject: [mg43614] Re: Forcing a Fit through a Data Point (Mathematica 5)
- From: pein <peter.pein at epost.de>
- Date: Tue, 23 Sep 2003 04:02:24 -0400 (EDT)
- References: <bkm7pa$rhj$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Hank Shih wrote: >Hello all. I have a set of data for a experiment and I want to create >the best fit line. Based on the x-y coordinate system, I need the line >to go through (0, 0) no matter what. The data is as followed: data = >{{0,0}, {.5,.25}, {1,.4}, {1.5,.5}, {2,.625}, {2.5,.84615}, {3,1}, >{3.5,1.0588}}. > >So far, to get the best fit I use: > >data = {{0,0}, {.5,.25}, {1,.4}, {1.5,.5}, {2,.625}, {2.5,.84615}, >{3,1}, {3.5,1.0588}}. > >abc = Fit[data, {1, x, x}, x] >Plot[abc, {x, 0, 5}, GridLines -> Automatic, AxesLabel -> {"Time (in > sec)", "Change in Distance (in cm)"}, > Epilog -> {PointSize[0.02], Map[Point, data]}] > >Is there a easier way to do this through Mathematica 5? If not, how can >I force it through that (0, 0) point? Thanks in advance > >Hank > > > In[1]:= data = {{0, 0}, {.5, .25}, {1, .4}, {1.5, .5}, {2, .625}, {2.5, .84615}, {3, 1}, {3.5, 1.0588}}; abc = Fit[data, {1, x, x}, x] cba = Fit[data, {x}, x] Out[2]= 0.05895\[InvisibleSpace] + 0.300596 x Out[3]= 0.324176 x