math

Are there any (somewhat) advanced mathematics Javascript libraries?

Are there any libraries knocking around that provide any additional general purpose math functions for Javascript? Say things like sums over a range, derivatives, integrals, etc. I can imagine that many things aren't possible, so even libraries that do rough approximations would be interesting. Thanks! Update: As mentioned below, I gue...

How many FPS should I have for updating a custom progress bar?

I just wrote a custom progress bar, it's single buffered and will remain so. How many frames per second are desirable for something like this? I don't want to waste too much CPU updating the screen unnecessarily. ...

What is the most efficient way to truncate a number for a specific accuracy?

What is the most efficient way to truncate a number for a specific accuracy? ...

How to map a long integer number to a N-dimensional vector of smaller integers (and fast inverse)?

Given a N-dimensional vector of small integers is there any simple way to map it with one-to-one correspondence to a large integer number? Say, we have N=3 vector space. Can we represent a vector X=[(int16)x1,(int16)x2,(int16)x3] using an integer (int48)y? The obvious answer is "Yes, we can". But the question is: "What is the fastest wa...

How to JSON serialize math vector type in F#?

Hello! I'm trying to serialize "vector" (Microsoft.FSharp.Math) type. And I get that error: Exception Details: System.Runtime.Serialization.SerializationException: Type 'Microsoft.FSharp.Math.Instances+FloatNumerics@115' with data contract name 'Instances.FloatNumerics_x0040_115:http://schemas.datacontract.org/2004/07/Microsoft.FSh...

What is different about C++ math.h abs() compared to my abs()

I am currently writing some glsl like vector math classes in c++, and I just implemented an abs() function like this: template<class T> static inline T abs(T _a) { return _a < 0 ? -_a : _a; } I compared its speed to the default c++ abs from math.h like this: clock_t begin = clock(); for(int i=0; i<10000000...

How to interpolate rotations?

I have two vectors describing rotations; a start rotation A and a target rotation B. How would I best go about interpolating A by a factor F to approach B? Using a simple lerp on the vectors fails to work when more than one dimension needs to be interpolated (i.e. produces undesirable rotations). Maybe building quaternions from the rota...

Python rounding problem

>>> num = 4.123456 >>> round(num, 3) # expecting 4.123 4.1230000000000002 I'm expecting 4.123 as a result, Am I wrong? ...

I've got my 2D/3D conversion working perfectly, how to do perspective

Although the context of this question is about making a 2d/3d game, the problem i have boils down to some math. Although its a 2.5D world, lets pretend its just 2d for this question. // xa: x-accent, the x coordinate of the projection // mapP: a coordinate on a map which need to be projected // _Dist_ values are constants for the projec...

CSG operations on implicit surfaces with marching cubes [SOLVED]

I render isosurfaces with marching cubes, (or perhaps marching squares as this is 2D) and I want to do set operations like set difference, intersection and union. I thought this was easy to implement, by simply choosing between two vertex scalars from two different implicit surfaces, but it is not. For my initial testing, I tried with t...

jQuery - I'm getting unexpected outputs from a basic math formula.

Hi I would like to start by saying I'd greatly appreciate anyones help on this. I have built a small caculator to calculate the amount a consumer can save annually on energy by installing a ground heat pump or solar panels. As far as I can tell the mathematical formulas are correct and my client verified this yesterday when I showed hi...

How can I write a power function myself?

Since I was 12, I was always wondering how I can make a function which calculates the power (e.g. 23) myself. In most languages these are included in the standard library, mostly as pow(double x, double y), but how can I write it myself? I was thinking about for loops, but it think my brain got in a loop (when I wanted to do a power wit...

Finding smallest angle between vectors in logarithmic time.

I have n=10000 10-dimensional vectors. For every vector v1 I want to know the vector v2 that minimizes the angle between v1 and v2. Is there a way to solve this problem faster than O(n^2)? ...

Algorithm for dividing very large numbers

I need to write an algorithm(I cannot use any 3rd party library, because this is an assignment) to divide(integer division, floating parts are not important) very large numbers like 100 - 1000 digits. I found http://en.wikipedia.org/wiki/Fourier_division algorithm but I don't know if it's the right way to go. Do you have any suggestions...

How to calculate point along a curve?

I am writing a custom animation for wpf and as a non math guy I have a couple questions... If I am given two Point3D's, the From and To, and assuming the origin is at 0,0,0 how do I calculate a curve between the two points? And once I have the curve 'plotted' and I know its length (how to do that too?) how can I calculate the x,y,z coo...

Finding coordinates of a point between two points?

Doing some 3D stuff in wpf- want to use a simpler test to see if everything is working (before moving to curves). The basic question is given two points x1,y1,z1 and x2,y2,z2 I have calculated the distance between the points. But how to find the coordinates of another point (x3,y3,z3) that lies on that line at some distance? I.e. if m...

Finding the Formula for a Curve

Is there a program that will take "response curve" values from me, and provide a formula that approximates the response curve? It would be cool if such a program would take a numeric "percent correct" (perhaps with a standard deviation) so that it returns simplified formulas when laxity is permissable, and more precise (viz. complex) ...

Flipping issue when interpolating Rotations using Quaternions

I use slerp to interpolate between two quaternions representing rotations. The resulting rotation is then extracted as Euler angles to be fed into a graphics lib. This kind of works, but I have the following problem; when rotating around two (one works just fine) axes in the direction of the green arrow as shown in the left frame here ...

Recursion problem in algorithm

I'm not sure if this is the right place to post this, but the problem actually belongs to a programming assignment. Solve the recursion: T(0) = 2; T(n) = T(n-1) + 2; Solution: T(n) = 2(n+1) Could someone please show me how they got to that solution? ...

How do I become better in math, after being a programmer for several years.

Possible Duplicate: How to improve my math skills to become a better programmer Basic Math Book for a Programmer I've had quite a weird career till now. First I graduated from a medical school. Then I went into marketing (pharmaceuticals). And then umm, after some time, I decided to go for my (till then) hobby and became a ...