Recent content by KStolen

Hey, thanks for the reply. Although I initially thought that I wanted the mean number of steps required to cover 50% of the cells, I think the number of steps required to achive a mean coverage of 50% of the cells might be better. If n is the mean number of steps required to cover 50% of the...

Unfortunately it's not a textbook problem - it came up in a programming project. Thanks to both of you - Ray and Stephen. I hadn't realized it was so difficult for the general case. I had hoped for a formula into which I could plug in my values, instead of having to determine the value of n...

Anyone?

I've got a problem I'd like to solve and I haven't done any probability in years. Here's the problem. There are two M*M grids of squares. An N*N mask is placed randomly on the second grid, such that it covers at least one square, but up to N*N squares. (i.e, the majority of the mask may lie...

That's right Mark. Because BLAS is written in Fortran, matrix row/column order is something you should be aware of when passing it matrices from C.

Well I realized what I was doing wrong, so I thought I'd put the description here for anyone who needs to know. lda, ldb and ldc (the strides) are not relevant to my problem after all, but here's an explanation of them : The elements of a matrix (i.e a 2D array) are stored contiguously...

Hi guys, I'm having trouble understanding how this routine works. cblas_dgemm is a BLAS function that gives C <= alpha*AB + beta*C where A,B,C are matrices and alpha, beta are scalars. void cblas_xgemm ( const enum CBLAS_ORDER Order, const enum CBLAS_TRANSPOSE TransA, const...

Well I can see how to get W(-0.1) by approximating with Newton's method: w_{n+1} = w_{n} - \frac{w_{n}e^{w_{n}}-(-0.1)}{e^{w_{n}} + w_{n}e^{w_{n}}} picking any number for w_{0} How do I know that W_{-1}(-0.1) exists if I don't graph it, as Char.Limit says? And how do I approximate W_{-1}(-0.1)?

Sorry, I'm not sure what is considered precalculus and what isn't, so hopefully this is in the right section. Homework Statement e^{0.1x} = x Homework Equations The Attempt at a Solution (1.105170918)^{x} = x Unfortunately there is no context to the question, so I have no idea what...

Homework Statement Find the work done in moving an object in the field F = (2xy+z^3)i + x^2j + 3xz^2k from (1,-2,1) to (3,1,4) Homework Equations I have found p, the scalar potential to be x^2y+xz^3 , but don't know how to proceed from here. Do I just plug in the values so that I...

Hi, this may seem like a silly question but here goes : Is there any difference between writing \partial x and d x when referring to partial derivatives? I've always used the simple d x for both because I don't like drawing the curvy d. To me, \partial N / d x and d N / d x are the same...

Sorry, I thought I was calculating the volume of something because I was integrating : (expression) dV. I read that \int\int\int f(x,y,z) dzdydz Represents the mass of an object, if f(x,y,z) is the density at (x,y,z). So I see if you integrated 1 dV, you'd get the volume...

Ah yes, that makes sense. It seems simple now. So e\int^{\pi/2}_{0}\int^{\pi/2}_{0}\int^{a}_{0} r^{6}Sin^{3}\vartheta Cos^{2}\vartheta Cos^{2}\phi dr d\vartheta d\phi is correct, and this finds the volume of one octant? This will then evaluate to e\int^{\pi/2}_{0}\int^{\pi/2}_{0} a^{7}/7...

I'm taking a Calculus class as an elective. This might not have been a good idea, but I'm stuck in it now. Here is a problem I have to do. My knowledge of basic maths is poor, so please be gentle and explain thoroughly! 1. The problem. Rewrite the following integral in terms of spherical polar...