Questions tagged [coordinates]
For questions related to coordinates. This includes number line, Cartesian, polar, cylindrical, spherical coordinate systems, etc.
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Spherical Polar Rotations | Is $(\theta + \pi, \phi + \pi) $ the same as $ (\theta + \pi, 0)$?
Question: I'd like some clarity on whether or not I can describe a $180^\circ$ rotation in spherical polar coordinates as $(\theta + \pi, \phi + \pi)$ affecting only the angles $\theta$ from the ...
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If I have x and y coordinates of a point along the arc, how do I convert that to a percentage of PI?
I am using Javascript to create shapes in canvas. I am creating an arc where you specify the start and end angle of the arc to show where along a circle the arc begins and ends. They are initially set ...
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Finding the coordinate of four points of imaginary intersecting lines which passes through end points of two intersecting lines
image
I want to find the coordinates of the points A,B,C,D where two imaginary lines intersect each other, where this imaginary lines passes through the end points of the two lines L1 and L2, the ...
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How to find coordinates of points on the circle, which is formed from intersection of two spheres?
What i did:
I can find the center of a circle (x, y, z) and its radius, but how to calculate certain coordinates (let it be 10 or 20 points) on the circle? I think each step for forming points on the ...
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Curl in non-orthogonal coordinates
How can I transform the curl operator into general non-orthogonal coordinates? I have tried to transform its orthogonal expression using the determinant but to no avail. I can't get the same results ...
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How to reflect in the line $y=x+4$?
I've recently come across this question in my book. It basically says that there are some points, $ABCDEF$ of certain coordinates and I need to find the coordinates of the reflected image on the line $...
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Find the coordinates of a point in a rectangle [closed]
Given a rectangle ABCD with sides 5 and 15. Let's assume that rectangle vertics have coordinates A(0,0) B(0,5) C(15,5) D(15,0). Point P inside rectangle is connected to the vertices of the rectangle ...
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Stumped on $\int_{-1}^1\int_{-\sqrt{1-x^2}}^\sqrt{1-x^2} \int_{x^2+y^2}^{2-x^2-y^2} dz\;dy\;dx$
I cannot express the following integral in spherical coordinates. It as though I am finding the volume between the solids. Any help will be appreciated.
$$\int_{-1}^1\int_{-\sqrt{1-x^2}}^\sqrt{1-x^2}...
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How to Derivate Divergence in Cylindrical Coordinates?
I am trying to derivate divergence in cylindrical coordinates, following is my derivation which is wrong and different from text book. I am confused why the derivation is wrong.
Denote $\nabla_x=(\...
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How to calculate the distance between two x and y points?
The euclidean formula $\sqrt{{(x_2 - x_1)^2 + (y_2 - y_1)^2}}$ works just fine when $ x{_1} = x{_2} \vee y{_1} = y{_2}$ but when calculating diagonals where $ x{_1} \neq x{_2} \wedge y{_1} \neq y{_2} $...
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Lie Bracket in curvilinear coordinates
When one works with Euler's equation in its vorticity formulation, one needs to work with the transport equation
$$(B\cdot \nabla)j=(j\cdot \nabla)B.$$
If one just uses cartesian coordinates this is (...
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Find coordinates with bearing from one point and distance from another.
I am trying to find coordinates of point $X$ if I know distance from point $A$ and bearing from point $B$, and a line from point $B$ intersects on a circle which radius equals the distance from point $...
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Understanding coordinates in a plane
I am learning animation. Position has two value, X and Y. X control left right, Y up and down.
So the tutorial am following: there the tutor positions the hands of a cartoon character in a way that ...
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Iterative Bilinear Interpolation on Quadrilateral
I've been working on a personal project where I am looking to do a manual NTv2 geographic coordinate transformation. As of right now, I'm trying to get my math correct before expanding it across an ...
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Finding $z \in \mathbb{C}$, with $z \neq -1, i$, such that $\operatorname{arg}(z+1)=\operatorname{arg}(z-i)$.
So for most locus questions, the algebra is fairly straightforward, I usually just substitute $z = x + yi$ into $z$ and see where that takes me. But for this question, I can't seem to get anywhere ...
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