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From: "Suman " <smnmehta.jsr@gmail.com>
Newsgroups: comp.soft-sys.matlab
Subject: Detect the change in slope
Date: Wed, 25 Sep 2013 08:50:05 +0000 (UTC)
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I have a data set that represent slope. I want to detect the point where there is a big change in the slope. 
The sample data set looks like this
  -0.9630
   -0.9151
   -0.9273
   -1.0041
   -0.8851
   -0.7854
   -0.7854
   -0.7854
   -0.6435
   -0.7266
   -0.6747
   -0.9420
   -0.8380
   -0.9420
   -0.8961
   -1.0714
   -1.0427
   -0.9828
   -1.2490
   -1.0714
   -0.9828
   -1.0041
   -0.9098
    1.1071
    2.1375
    2.0701
    2.1112
    1.9513
    1.8925
    1.9757
    2.0344
    2.1375
    2.1815
    1.9974
    2.0701
    2.2455
    2.0989
    2.1815
    2.2318
    2.2318
    2.2974
    2.1815
    2.3562
    2.3562
    2.6345
    2.6012
    2.6779
    2.7150
    0.0204
   -1.0714
   -1.0041
   -0.7854
   -0.8380
   -0.9420
   -0.8380
   -0.7328
   -0.6747
   -0.6747
   -0.8851
   -0.9420
   -0.9420
   -0.9601
   -1.0041
   -1.1071
   -1.1071
   -0.9828
   -1.0191
   -1.3045
   -1.0041
   -1.0714
    1.0273
    2.1112
    2.0701
    2.1375
    2.1815
    2.2974

I find it difficult to handle this because of the changing sign.
Hope I can get some help.
Thanks in advance.