tangent to a curve
tangent to a curve
(OP)
Excel spreadsheet : while designing a curve on a diagram (X & Y data known) how can I draw the tangent in a specific point ?
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RE: tangent to a curve
How about posting your x,y data and the x,y point for the tangent.
Skip,
_{ Just traded in my OLD subtlety... for a NUance!}
RE: tangent to a curve
Dik
RE: tangent to a curve
Dik
RE: tangent to a curve
TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731376: EngTips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.engtips.com/forumlist.cfm
RE: tangent to a curve
Works for a circle, or pretends it's a circle at the point of tangency (as any other tangent would). The two points are as follows, one defines the centre of the circle and the other defines the point of tangency. A line through them determines the radius of the circle and also the slope of the line. The inverse gives you a slope that matches the tangent.
The equation of the line is created by using a known point (ie, the tangent) and the slope of the tangent. From way back, y = mx + b, for a slope intercept definition of a line. By using the point data for the point of tangency, the function yields a 0 for the solution.
If it's just an arbitrary curve (not a circle) you have to determine the 'centre' for this and this would be the inverse to the derivative at the point. The centre of this 'circle' would fall anywhere on that line, but the point of tangency would remain.
Dik
RE: tangent to a curve
Dik
RE: tangent to a curve
There are of course infinitely many different curves that may be drawn through any finite number of points, but a reasonable approach is often to generate a cubic spline, which is a series of cubic curves where the slope and the curvature are continuous at each point.
See https://newtonexcelbach.com/2009/07/02/cubicsplin... for an Excel spreadsheet that will generate a cubic spline through any xy data (listed with increasing x), and will return the y, slope and curvature for any x value.
Also search the blog for "cspline" for further articles with different types of cubic spline.
The latest version of the spreadsheet may be downloaded from:
http://interactiveds.com.au/software/CSpline2.zip
Doug Jenkins
Interactive Design Services
http://newtonexcelbach.wordpress.com/
RE: tangent to a curve
TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731376: EngTips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.engtips.com/forumlist.cfm
RE: tangent to a curve
Doug Jenkins
Interactive Design Services
http://newtonexcelbach.wordpress.com/
RE: tangent to a curve
For a circle, you only need to know the centre point of the circle and the tangent point... no other points are necessary.
Dik
RE: tangent to a curve
Dik
RE: tangent to a curve
I know, but there is nothing in the OP to suggest that they are dealing with a circle.
Doug Jenkins
Interactive Design Services
http://newtonexcelbach.wordpress.com/
RE: tangent to a curve