3d Definition and 1000 Threads

hi, so this is actually for a program I'm writing, but it's definitely more of a math question than a programming question. basically, i have an object that gets detected by a webcam attached to a computer. the object is just a piece of paper with a pattern on it, so it is, for the purpose of...

When James Cameron made Titanic in 1997 it touched the hearts of people all around the world. I was a kid at that time knowing not much about love, pain, loss of loved ones, injustice around us, it still stands as one of my favorites; and it is always a new experience each time I see it. Rarely...

Currently I am using a graphying application called "Autograph" and modeling a building with a dome shaped roof on top. I need to define parabolic shapes in 3d system. But i can't do it ( my math knowledge is pretty elementary) What would be the basic parabolic function in 3d that i can base...

I have a temperature distribution T = T(x,y,z). I want to visualise it in MATLAB ( such that the colour(s) used by MATLAB in plotting should give me an idea of depth of temperature i.e whether its high or low compared to its neighbouring points). Please help

i have the normal vector of a polygon face, and an object i wish to align to it by rotating it on XYZ. my up vector is (0,1,0). been trying to figure it out by using CrossProduct but i never get the right results. I already have CrossProduct and Normalize functions so I don't need the math for...

Hey guys, quick question, I am in a little bit of a bind. I need a 3D plotter to post-proc some CFD runs at home. I have typically used plot3d in the past, but am having trouble getting it to compile on my machine (Ubuntu 10.04). I did a search and there's another program which can handle...

I was tasked with making some animations of simple ODEs and PDEs in MATLAB for use in an undergraduate class. (Vibrating string, Heat Equation, Navier-Stokes)... I wrote some code and plotted some graphs, but I'm not seeing an option to animate along an axis in 2010a. Maybe I'm blind and...

i'm having trouble creating a arc for check for collision similar to a grenade launcher type weapon and am not very good at math :/ i have the player position and the target position, now i just need to check every so often (let's say .1 units) along the outside of my ellipse to see if my...

Hi, I'm helping my friend with a space combat game he is programming. What I'm trying to figure out is how to model the collisions between spheres in 3D. So far I've figured out how to calculate final velocities of 2 colliding spheres using conservation of linear momentum. I found a...

Hello, I was just wondering if anyone knows if there's a way to save a 3D plot in Matlab (eg a "surf(x,y,z)" plot) so that it is viewable outside of Matlab and so that you can still rotate the view etc? And in particular, so it can be viewed in a webpage? Something like LiveGraphics3D? I don't...

Ok so I'm writing a 3D game that uses impulse to determine how things behave when they collide. In this game I have two cubes. Now the shape of each cube is defined by 9 spheres, sort of like this: http://mark.reid.name/images/figures/high-dim-3d.png Though in my game the middle sphere is...

Do 3d glasses use diffraction to work , because the ones i read about did not say anything about diffraction , but i shed a laser through my 3d glasses and it diffracted it perfectly on the wall , it had a center bright spot and then equally spaced dots from the center out .

Hello, just got done taking a test and one problem kinda confused me. Homework Statement f(x,y) = e^x cos y find local min/max and saddle points Homework Equations fx = e^x cos y fy = -e^x sin y The Attempt at a Solution I answered that there were no critical points for...

Homework Statement Giving 2 closed curves in 3-dimension space C1 and C2, prove that:\oint _{C1} \oint _{C2}\frac{(\vec{dl_2}.\hat{r_{12}})\vec{dl_1}}{r^2_{12}}=0 Where: _ \vec{dl_1} and \vec{dl_2} are the vector elements of the curves C1 and C2 respectively. _ r_{12} is the distance between...

I'm writing a game that involves collisions with spheres. Anyway each sphere has both angular and linear velocity. These two spheres collide. I need to find the direction of the impulse between them (if that's the right wording). I tried just subtracting their linear velocity components like...

Hello. I was asked to import a number of data to mathematica from an output file for wien2k (based in fortran). The thing is, I have to draw a graph that considers a matrix full of data in three dimensions, but the graph itself should only have two parameters. To sum up: how to represent 3D data...

Homework Statement [PLAIN]http://img708.imageshack.us/img708/1344/trig.jpg The angle c is separated from a 2d plane by angle b (perpendicular to the 2d plane). Angle a is angle c projected onto the 2d plane. What is a in terms of b and c? Homework Equations The Attempt at a...

hi everyone... i am dong my project designing a 3d solid state hi everyone... i am dong my project designing a 3d solid state accelerometer.The accelerometer should detect and measure steps. Can anyone of you help regarding the design of it...

I have a 4072x22x10 matrix. I am trying to calculate the RMS of the 4072x22 matrix but am unable to do so. The worst case scenario would be to individually calculate the RMS value of each element but that would require a number of loops and I don't want to do so. Is there any easier way to get...

The Hamiltonian of the diatomic molecule is given by H = p1^2 / 2m + p2^2 / 2m + 1/2 k R^2, where R equals the distance between atoms. Using this result, given in standard texbooks, I keep geting C = 9/2 kT instead of 7/2 kT for heat capacity. I've traced down my problem to the potential energy...

Homework Statement [PLAIN]http://img208.imageshack.us/img208/5445/problem3.png All problem info contained in the image. Homework Equations equations of relative motion? The Attempt at a Solution Frankly I am stuck on where to begin. I would normally make a free body diagram...

This is my first post and I'm pretty much lost when it comes to linear algebra. I am a programmer and I am currently working on converting a 3D model format for personal purposes. I am having trouble figuring out an equation. If you want the background of what I am doing I'll be happy to explain...

Hi, I have to find the 'stationary position' of a particle of mass m and charge q which moves in an isotropic 3D harmonic oscillator with natural frequency \omega_{0}, in a region containing a uniform electric field \boldsymbol{E} = E_{0}\hat{x} and a uniform magnetic field \boldsymbol{B} =...

Homework Statement If I consider a 3 dimensional problem related to a spring pendulum (a mass attached to the end of a spring of constant k and the other end of the spring remains fixed) and I want to find the equations of motion of the mass (for several initial conditions), what system of...

QED in 3D --> QED in 1D, what changes? Can we have massive charged and massless fields which interact in one space dimension? What might the interaction term look like? Thanks for any help!

I was thinking that if i have for example a boost in the direction of x, then the boost should be equivalent to an hyperbolic rotation of the y and z axes in the other direction. I don't know if it's true or not. Then I want to know if somebody knows this result or why is false? I was...

Hi all, When viewing 3D films, you are given a pair of glasses without which, the pictures are bad and blur . So what is the principle of the technique? Is that polarization of the light? Thanks

For a personal project, I am analysing the physics in the Source video game engine and comparing it with real life. I have set up in the engine a platform which increases in inclination from 0 to around 70 degrees. On this platform there are four, equally weighted cubes each with a...

Homework Statement I'm using MATLAB show the path of a projectile fired directly up(directly out from the center of the earth) from 41 degrees north latitude. Air resistance, variation of gravity cause by height, and the centrifugal force are for now ignored. What I'm trying to figure out...

Homework Statement A particle with mass m moves in the potential: V(x,y,z) = \frac{1}{2} k(x^{2}+y^{2}+z^{2}+ \lambda x y z) considering that lambda is low. a) Calculate the ground state energy accordingly to Pertubations Theory of the second order. b) Calculate the energies of...

Using "surf" function to plot slices of a 3D matrix Hello I have a 100x100x100 matrix called "A" and want to plot 2D slices of it to get a feel of where the global minima are (since there is no other way which I know of visualising it... is there?) If I take a slice of the third...

Homework Statement Find the area of the parallelogram with vertices: P(0,0,0), Q(-3,0,-1), R(-3,1,0), S(-6,1,-1) Homework Equations A=BH The Attempt at a Solution I think I know why this is incorrect, but i don't know what else to try. I found vector PQ and called it a...

I won't post the actual problem with numbers, I just need some direction. My teacher never went over this part of the webwork in class, and we haven't touched on it in physics either. "a" and "b" are both 3D vectors. 1.) I am supposed to find the component of "b" along "a" 2.) I am...

I managed to make a movie which displays my research results as a 3Dplot which varies over time. Now I would like to ad the actual time in my movie. Say I have data from 12:00 until 14:00, can I make some kind of counter so I can see what time it is in the movie? Hope someone can help me out...

Hi, i need to pass a function in MATLAB a few parameters, one of the parameters is an equation such as : sin(x)-cos(y) and have it make the 3d graph, i have no problem setting up the meshgrid etc and getting it to work running strait from the m-file function graph = graph(f) n=20; x =...

I have created such a thread in the past but it was misinterpreted and I haven't been given the help I needed , this time I shall explain more about what is going wrong through a figure . sorry for my bad english. topic: when a 3d body is going at constant velocity in a straight line and...

Online integrator: http://www.wolframalpha.com/ \int \int (x,y,z) \times (x,y,z) \times (x,y,z) \int_{L1} \int_{L2} (dl1,0,0) \times (dl2,0,0) \times (0,-1,0) What would be correct syntax to evaluate this double integral? I tried these, but they produce wrong result: try...

I have computed the flow past a golfball and I am trying to calculate the shear stress on the surface of the golfball but I am having trouble figuring out how the wall shear stress is defined on 3D complex surfaces. When I am on the main part of the golfball that it is similar to that of the...

ok. this is an easy enough thing to prove in one dimension but my question seems to be 3 dimensional and it's causing me some hassle: show the expectation value of the kinetic energy in a bound state described by the spherically symmetric wavefunction \psi_T(r) may be written \langle...

Hi, I'm tring to explore magnetic field of the contact system, but when I set the current on a face, i have the next error: "An external terminal must border the edge of the problem region and coincides with the surface of a 3D object" I solve this problem when I set region overlap with this...

This is not really homework, just a project I'm toying with in my sparetime. I'm doing some Path Integral Monte Carlo simulations, for now just for the 1D quantum harmonic oscillator. Anyways, currently I compare my results to the analytic mean energy of a 1D quantum harmonic oscillator, given...

Homework Statement It's been a while since I've done this stuff D: So Given Points A(a,1,0), B(1,b,0) and C(1,0,c) with |AC|=|BC|=|AB| Find the points algebraically Homework Equations Unfortunately, i don't have much knowledge on this. I am sure there's a 3d point slope style...

I was given the question, If u=ai+2j+4k and v=3i+bj+k, calculate a and b in a textbook from school (revision for a test). Any thoughts?

Hello, I am designing a FPS in which I am planning for the trajectory of a bullet to follow this formula here: http://en.wikipedia.org/wiki/Trajectory#Derivation_of_the_equation_of_motion" I am not adding any drag or resistance a the moment, but the problem is, that all these trajectory...

Hello, I am trying to write an algorithm to calculate the Least Squares Fit Line of a 3D data set. After doing some research and using Google, I came across this document, http://www.udel.edu/HNES/HESC427/Sphere%20Fitting/LeastSquares.pdf (section 2 in page 8) that explains the algorithm for...

This is not homework. I am reviewing all of the calculus that I have forgotten. Howard Anton's Calculus w/Analytical Geometry, 5th ed., section 4.1, prob #32: A police helicopter is flying due north at 100km/hr and at a constant altitude of 1/2mi. Below, a car is traveling west on a...

Greetings: I am trying to help my son graph some data for a colorful 3D lattice or point distribution chart to display for a science fair project. We measured magnetic flux with a hall sensor on an x,y,z axis pedestal. We took data from measurements of cartesian coordinates in 3 dimensions...

I have a cube with sides l and therefore a total volume of l^3. The E-field is ax + by + cz where a, b, and c are known constants. It says to find the total E-field. The answer is (a + b + c)*l^3. I have no idea how they get this. I tried summing up all of the sides separately bit I kept getting...

Homework Statement Given the space curve r(t)=<t^2,(2t^3)/3,t>, give the parametrized equation for the osculating circle along the trajectory at r(p). I should note this is so I can give a plot of the circle in Winplot, which is a free grapher/plotter type program. Homework Equations...

A 3D vector is completely defined by its three Cartesian coordinates, which specify the position of the terminal point of the vector. But shouldn't there be 3 other coordinates to specify its starting point? I understand vectors have no location, and therefore 3 numbers is enough. But is this...