**curvature and radius of curvature of a plane curve**Hello,
I want to calculate the local curvature (or radius of curvature) for
a few point on outline on a picture, but how the hell am i suppose to
do that ?
Thanks,
Kenneth
Of course i want a way to do it in matlab...
In article <ef5d840.-1@webcrossing.raydaftYaTP>, bird
<djbirdnerd@hotmail.com> wrote:
> Hello,
>
> I want to calculate the local curvature (or radius of curvature) for
> a few point on outline on a picture, but how the hell am i suppose to
> do that ?
>
> Thanks,
> Kenneth
------------------
If your "outline" points' coor...

**curvature and radius of curvature of a plane curve #2**Hello,
I want to calculate the local curvature (or radius of curvature) for
a few point on outline on a picture, but how the hell am i suppose to
do that ?
Thanks,
Kenneth
...

**curvature radius**Hi,
I've been trying to find the curvature radius of my data set.
x1=[x1(1) x1(2)....]
y1=[y1(1) y1(2)....]
x1 is just numbers, and the interval between x1(i) and x1(i+1) is constant
like x1= [1 3 5 7...]. dx1=2
y1 is a vector (y coordinate of x1) which are variables.
what I did (for getting curvature radius for each point) is as follows.
suppose we wanna get curvature at x1(2)
k1=(y1(3)-y1(1))/dx1 -> 1st derivative
k2=((y1(3)-y1(2))/dx1-(y1(2)-y1(1))/dx1)/dx1 -> 2nd derivative
r= (1+k2^2)^(3/2)/abs(k2)
In this way, I could get r in term of y1(1), y1(2), ...

**Radius of curvature**I have an arc of data points (scattered in x,y,z). The z value is
approximately constant for a given y location. I want to know the
radius of curvature of the arc. How can I find this?
Thanks
Chris
Chris wrote:
>
>
> I have an arc of data points (scattered in x,y,z). The z value is
> approximately constant for a given y location. I want to know the
> radius of curvature of the arc. How can I find this?
>
> Thanks
>
> Chris
Knowing the coordinates of the data values you can compute the total
arc length and the cord length (You may want to experiment with the
many ...

**Radius of Curvature**I need a better definition of radius of curvature.
The "standard" definition can be found in, for example,
http://mathworld.wolfram.com/Curvature.html. There, curvature "K" is
defined as "d(phi)/dS", and radius of curvature is defined as "1/K".
This appears to be derived from the basic relationship
S = R*phi
where S is the distance along the circular path, R is the radius of
curvature, and phi is the angle. Differentiating, we get
dS = R*d(phi) + dR*phi
If R is assumed to be constant, then dR*phi=0 and
dS = R*d(phi)
1/R = K =...

**2D maximum curvature**Dear all
I am trying to find the point of maximum curvature on a 2D curve.
This should be very simple I think! Does anyone have a code for this?
Many thanks
Dorothy Cowie
Dorothy Cowie wrote:
>
> Dear all
> I am trying to find the point of maximum curvature on a 2D curve.
> This should be very simple I think! Does anyone have a code for
> this?
> Many thanks
> Dorothy Cowie
----------------------
If your curve is given by two row vectors, x and y, you can
approximate its curvature at each point by the reciprocal of the
radius of a circumscribing triangle with that point...

**radius of curvature from a grid**hi all
iam new to matlab and have a query in reg to radius of curvature.I did read the other posts in reg to the same topic, but would want your suggestions/help anyways
the height of a surface is given in a grid format i.e
x y z (height)
0 0 2
0 1 4
0 2 3
......
.......
with z not directly related to x and y and the equation of dependence i.e f(x,y) is not known
the gradient was estimated by the del operator
The radius of curvature is to be calculated;
any help would be heartily accepted
...

**find maximum radius of the object**Hi all,
I need your help
how to find maximum radius of the object where the object can regular (like circle, rectangle, etc) or irregular object.The radius count from center.
please help me...
regards
...

**maximum curvature of Bezier curve**Hello,
Is there a formula for estimation of the maximum of the bezier curve
curvature from the control points (for third and second order bezier
curves)?
I do not want to solve the polynomial equation for that; I just want
an approximate result which could be quickly calculated.
Why I need this? I am drawing a shape, which is result of drawing of
bezier curve with thick pen. The shape is drawn as a set of filled
triangles. I would like to estimate bezier subdivision depth to have
outline of the figure looking smooth enough on a raster device.
Thank you,
Sergey Tolstov
"Sergey Tolstov&...

**Local radius of curvature for a surface?**Hello all,
I have a surface (can plot it with surf within MATLAB) and I am
trying to calculate the local radius of curvature along a tangential
direction to the surface at each point (of my surface).
The surface is actually the outer surface of a human eye
reconstructed in 3-D.
Anybody would know how to do that with a simple way within MATLAB. I
will appreciate any help here.
Thanks a lot,
Michael
In article <ef5cef9.-1@webcrossing.raydaftYaTP>, "Mick The Ouf"
<miikkee@gmail.com> wrote:
> Hello all,
>
> I have a surface (can plot it with surf within MATLA...

**radius of curvature for wind tunnel**Hi im designing a wind tunnel and i have this curve for a part called the contraction.
Ive got this function F(x)=-1.7068x^3+1.96947x^4-0.60599x^5+0.45
im using the limits of x>=0 and x<=1.3
y>=0 and y<=0.5
im trying to find the radius of curvature at two points of the curve to be able to enter the curve into a CAD program and then to be manufactured, but im confused how to do that. The first curve is convex leading to a straight line then to a concave curve. Is there a way of finding the coordinates of the center of curvature for this curve and radiu...

**Plotting curvature and display radius**Hi,
I've the following problem and I was unable to find a solution on my own...
I define a track with its curvature (or radius, its 1/curvature), and I want to plot the radius. As I have some sections in alignment, my curvature is 0 and my radius infinite.
So, I want to plot the curvature (value 0 in alignment, and increasing with the decrease of the radius) but with the radius values on Yaxis and when using the data cursor.
Is this kind of things realizable ?
Thanks a lot ;)
...

**find maximum radius of the object #2**Hi all,
I need your help
how to find maximum radius of the object where the object can regular (like circle, rectangle, etc) or irregular object.The radius count from center.
please help me...
regards
"zahra daffa" <zahra_daffa@yahoo.com> wrote in message
news:hcr3vp$hqg$1@fred.mathworks.com...
> Hi all,
> I need your help
>
> how to find maximum radius of the object where the object can regular
> (like circle, rectangle, etc) or irregular object.The radius count from
> center.
>
> please help me...
>
> regards
Which object are you talking...

**radius of curvature and discrete data question**Hey,
I have discrete data points (as x and y coordinates) which track the
movement of an object over time. I need to calculate the radius of
curvature of the set (over the time of the experiment). Is it
possible to use the rcurve command from the Mapping Toolbox for this?
Is there a better way? I have ~16 coordinates for each track, and
need to calculate the radius of curvature for 50 to 100 tracks.
Thanks in advance.
TGte wrote:
>
>
> Hey,
>
> I have discrete data points (as x and y coordinates) which track
> the
> movement of an object over time. I need to calculate...

**radius of curvature for wind tunnel #2**Hi im designing a wind tunnel and i have this curve for a part called the contraction.
Ive got this function F(x)=-1.7068x^3+1.96947x^4-0.60599x^5+0.45
im using the limits of x>=0 and x<=1.3
y>=0 and y<=0.5
im trying to find the radius of curvature at two points of the curve to be able to enter the curve into a CAD program and then to be manufactured, but im confused how to do that. The first curve is convex leading to a straight line then to a concave curve. Is there a way of finding the coordinates of the center of curvature for this curve and radiu...

**Fast maximum curvature calculation for a 3d bezier curve**Hi,
I have been looking at efficient ways of calculating the maximum
curvature of a bezier curve, and so far have not found anything which I
believe would be fast enough. I need to do this test for a hundreds of
splines to determine if they are valid or not (curvature is less than
some value). The method does not need to be a 100% accurate. Even a
good close approximation would do.
At the moment the fastest I could think of was subdiviosion using a
flatness test and then calculating the curvature of the end points (end
point curvature calculation does not seem to bad). In this way I am
calcu...

**Radius to Radius**I must be missing something simple, I guess. I have a part I'm trying to dimension that has a radius on both ends. Flat
part with no straight sides where I want to dimensions. In Acad, you could type "quad" from the command line and pick the
extreme edge of a radius, the using the "quad" command again, pick the opposite radius for a dimension from extreme to
extreme. Is there something I'm missing? BTY, I'm using 2K3
R. Wink
Hello towarts you.
What you are able to try is able be done. Make first one dimensions from
arc from to arc, but recalling to make p...

**maximum**I'm looking for maximum func implimintation, i mean that i need to see
her kod
komukc wrote:
> I'm looking for maximum func implimintation, i mean that i need to see
> her kod
fun x y ->
if x > y then x else y
--
Dr Jon D Harrop, Flying Frog Consultancy
Objective CAML for Scientists
http://www.ffconsultancy.com/products/ocaml_for_scientists
...

**RADIUS**What's the point of a RADIUS when one can use the Access Point to act
as an authenticator and process any authentication dicisions needed?
...

**Maximum**Hi:
Sorry, I had to start a new thread on the same subject, because some
imbecile decided to add OT crap.
I am asking a technical question. No offense but please don't bring in
irrelevant topics [such as budget]. I was asking in terms of quality
for human auditory perception.
What are the maximum *practical* limits of the following for an FM
synth:
1. Number of voices:
2. Operators per voice:
3. Number of channels**:
**Yamaha's OPL3 has 18 channels
quote from http://en.wikipedia.org/wiki/Yamaha_YMF262 :
"Twice as many channels (18 instead of 9)"
Obviously the "...

**Maximum**Hallo an alle!!
Ich habe folgendes Problem: Ich habe eine Funktion f(a,b) definiert,
die mir bei gegebenen a und b ein Doppelintgral berechnet, wobei ein
Paramter a als Grenze dient und der andere als Paramter in der
Funtion.
Nun will ich jene Werte von a und b im einem vorgebenen Intervall
haben, wo das Integral den maximalen Wert annimmt.
Ich habe das jetzt so gel=F6st:
M=3Dzeros(100,100);
for i=3D1:100
for j=3D1:100
M(i,j)=3Df(i/10,j/10);
end
end
v=3Dmax(M);
l=F6sung=3Dmax(v)
Das funktioniert, ist aber sehr uneffizient, da er lange rechnet. Das
Doppelintegral habe i...

**Curvature control vs Curvature tangency**.....and the million dollar answer is.....(ie on a spline what is the
difference between how it control the look of it?)
As I understand it, curvature control let you specify the curvature along
your spline while curvature tangency is a constraint that ensures the
curvature at the end of the spline matches the curvature of the other curve
at the connection point (called C2-continuity, vsible with zebra stripes)
Did I win the million ?
--
Philippe Guglielmetti - www.dynabits.com
Sorta. In normal unflavored parlance G1 (tangency) means
there is not a sharp edge at the common edge shared b...

**RADIUS ?**Hi
I am trying to set up an authentication system for my home wireless network
that is more secure than a fixed encryption key.
Is a RADIUS server the solution for it ?
I have been trying to set up freeradius (version 0.9.3) on my desktop all
morning but it always fails :
./configure --prefix=/usr/local/freeradius
--with-mcrypt=/usr/local/lib/libmcrypt/
--with-mhash=/usr/local/lib/libmhash/ --with-ltdl-lib=/usr/lib
--with-system-libtool --with-threads --with-thread-pool
--enable-ltdl-install --localstatedir=/var --sysconfdir=/etc
--with-rlm-rlm_eap_tls-lib-d...

**Curvature**Hi,
Is there a function that computes curvature along a curve?
Thanks
sharma
sharma wrote:
>
>
> Hi,
> Is there a function that computes curvature along a curve?
> Thanks
> sharma
Requesting the same question again!
Any function that computes curvature along a curve?
Thanks
sharma
...