167 reputation
9
bio website simonwinder.com
location Seattle
age
visits member for 2 years, 8 months
seen Aug 12 at 23:11

I am a software developer and science researcher who is a specialist in computer vision. I worked for Microsoft Research for many years. Now I am an independent consultant and I am starting a robotics company. I work on iOS, OpenGL platforms and also on Windows. I have lots of experience writing fast code using SSE, GPU etc.


Sep
24
awarded  Autobiographer
Jul
5
asked Linear Probability Density Transformations
Jun
22
awarded  Tumbleweed
Jun
20
awarded  Excavator
Jun
20
revised How to determine the step response using convolution of the signal's impulse response?
fixed math formatting
Jun
20
suggested suggested edit on How to determine the step response using convolution of the signal's impulse response?
Jun
15
asked Adaptive whitening / decorrelation
Mar
5
comment Finding a simple spline-like interpolating function
OK well you'll be pleased to know that your answer is now incorporated into my iPad app.
Mar
5
comment Finding a simple spline-like interpolating function
Actually my previous statement was false as I realize that introduces a singularity at $\alpha = 0.5$. (Its amazing how little appears on a screen when you have Infs in a vertex shader.) And I guess robotbugs could be both:)
Mar
5
comment Finding a simple spline-like interpolating function
OK thats great because its just $\frac{kx}{x+c}$ which is very few math operations. I can precompute the two constants.
Mar
5
accepted Finding a simple spline-like interpolating function
Mar
5
awarded  Commentator
Mar
5
comment Finding a simple spline-like interpolating function
You have a mix of $k$ and $x$ in there. Are they supposed to be the same variable?
Mar
5
comment Finding a simple spline-like interpolating function
Also what did you use to display such a nice graph on here? I was wondering how to get a diagram in my original post. Last time I tried to post something though I did not have enough standing on the forum to post images.
Mar
5
comment Finding a simple spline-like interpolating function
Thanks, thats exactly the form of curve I was looking for. I can certainly live with a square root function. Many thanks!
Mar
5
comment Finding a simple spline-like interpolating function
I'm currently using code: if(d<alpha) d = (1.0-alpha)*d/alpha; else d = (1.0-alpha)+(d-alpha)*alpha/(1.0-alpha); to do a simple 2 piece linear interpolation. The point of my question is finding something smoother and possibly faster to compute.
Mar
5
comment Finding a simple spline-like interpolating function
I tried using a b-spline with three control points at $(0,0)$, $(\alpha,1-\alpha)$, and $(1,1)$ and it looks ok when plotted but the problem is its in a parametric form depending on $t$ and getting a simple $y=f(x,\alpha)$ out of it is painful.
Mar
4
asked Finding a simple spline-like interpolating function
Sep
22
revised Minimize $||Ax-b||$ but for $A$, not $x$
added 2 characters in body
Sep
20
accepted Minimize $||Ax-b||$ but for $A$, not $x$