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seen Dec 11 at 7:00

Jun
18
comment Plotting an integral of a function in Octave
it's been so long since I asked this question, I don't remember the use case any more ;-). The only thing I remember is that I switched from Octave to C#... Thanks anyway for your effort.
Jan
28
comment Numerically calculate the second “left hand” derivative
After having tested Hagen von Eitzen's approach, I realized that your approach can also be seen as a linear extrapolation of two former second derivatives (which are quite accurate as it seams). This makes it clear to me why the error can be so large given a large change in the second derivative and a big gap between the measurements (i.e. large $h$).
Jan
28
comment Numerically calculate the second “left hand” derivative
@HagenvonEitzen: Your proposal leads to the same result as gammatester's
Jan
28
comment Numerically calculate the second “left hand” derivative
@HagenvonEitzen: If I get you right, you suggest calculating $f''(x-h)$ and $f''(x-2h)$ using a central difference and extrapolate these values to $f''(x)$?
Jan
28
comment Numerically calculate the second “left hand” derivative
Thanks for the formula. See my updated question.
Nov
21
comment Plotting an integral of a function in Octave
How would you rewrite the function g? g = @(x) (quadcc( 0:0.1:x, f(0:0.1:x))); doesn't work. The plot results in an error ` plt2vv: vector lengths must match`.
Oct
31
comment How to solve an overdetermined system of point mappings via rotation and translation
I mixed up two different things: transformation error and error induced due to the "erroneous" transformation.
Oct
31
comment How to solve an overdetermined system of point mappings via rotation and translation
Thanks for correcting the Mathjax. I didn't see the result in my edit since our virus scanner blocked the mathJax script ;-). I hope it'll improve in future posts...
Oct
31
comment How to solve an overdetermined system of point mappings via rotation and translation
Since you use the trace I assume I have to use the Frobenius norm to follow your steps. Since I'd like to measure the transformation error for a given set of points according to the 2-norm, will this work?