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From: "Stephen " <mulan_nuri@yahoo.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: tangent line from curve graph
Date: Sun, 22 Feb 2009 02:22:02 +0000 (UTC)
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Thanks for response, Matt Fig.
I really not good in matlab, so can u explain a little bit about forward difference, backward difference and secant. I'm not really understand.
I already tried spline, but seems it shows the values of P, not dP/dt.
Maybe i wrong in giving information earlier but what i wish to obtain is the value of dP/dt at specified t and in my mind, this value can be obtained by finding tangent line (or slope) at that specified t.
Meaning that, the tangent (or slope) should represents as dP/dt.

Sorry,if i already misunderstood your opinion.