... Animation . Arrow . ... I created the first animation by running Script-Fu / Animators / Fire on the head of an arrow. ... I merged the animation with the background image, and specified a final X offset of -128 (the background is 128 pixels wide). This results in an animation with a nice moving background. Note that you can also use a background that is wider than the image, as long as you specify the width of the background for the final X offset if you want the final animation to loop. ...

project - project data along a line or great circle , generate a profile track, or translate coordinates. project [ infile ] -F flags -C cx / cy [ -A azimuth ] [ -Dd|g ] [ -E bx / by ] [ -G dist ] [ -H [ nrec ] ] [ -L [ w ][ l _ min / l _ max ] ] [ -M [ flag ] ] [ -N ] [ -Q ] [ -S ] [ -T px / py ] [ -V ] [ -W w _ min / w _ max ] [ -: ] [ -bi [ s ][ n ] ] [ -bo [ s ] ] project reads arbitrary ( x , y [, z ]) data from standard ... H Input file(s) has Header record(s). ...

A spherical meteorite of radius 3m enters the Earth's atmosphere at an altitude of 100km and a speed (relative to the Earth) of 30 km/s. The atmosphere slows it down, so when it hits the Earth's surface it is travelling at only 1 km/s. If half of the heat generated as it passes through the atmosphere is absorbed by the meteorite, how hot will it be when it is about to land? ... However, the number I calculated (500,000 K) is correct, as is the discussion that follows it. ...

... new: . ... Python 2.6.2 + most up-to-date modules (December 2009) . ... pyQC script structure . ... The current installation of python and its associated modules on our DFO machines is extremely old (i.e. python 2.4.2 was released in Sept. ... The new python executable lives in: /qcdp/bin/python . ... The first figure shows the execution times for the old python installation, while the second figure shows the execution times based on scripts running the python 2.6.2 installation with the new modules...

... Circle rotations. ... Symbolic dynamical systems: sequence spaces, Markov chains, adding machines. Birkhoff recurrence theorem. ... Tent map. ... Expanding maps of a circle. ... Topological entropy. ... Finiteness of entropy for Lipschitz self-maps. Entropy for symbolical dynamical systems. ... Entropy for one-dimensional maps. Entropy for expanding maps and the Misiurewicz-Przytycki theorem. ... Structural stability of expanding circle maps. ... SRB measures for expanding maps. ...

Astronomy Discussion Forums . ... Need All Claims Be Tentative? ... Here is an issue: does a particular representation correctly match the pattern it is claimed to represent went viewed by method 'x', within the limits of precision given by the definitions of the original pattern, the representation, and the method of viewing (x)? ... www.astronomy.net . ... Forum posts are Copyright their authors as specified in the heading above the post. "dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET" . ...

... will give a .\" real vertical bar. ... xpaset xpa # send to xpa \& cat xpa.c | ... You also can use ctest to do the same thing, or to iterate: .PP .Vb 4 \& ctest -s -l 100 xpa # send to xpa 100 times \& ctest -s -l 100 "xpa*" # send to xpa and xpa1 100 times \& ctest -g -l 100 xpa # receive from xpa 100 times \& ctest -g -l 100 "xpa*" # receive from xpa and xpa1 100 times .Ve .PP More options are available: see the stest.c and ctest.c code itself, which were used extensively to debug \s-1XPA\s0. ...

... Basic time functions . ... Example 2: Set a random number seed . ... Uses of time functions include: . ... time_t time(time_t *tloc) -- returns the time since 00:00:00 GMT, Jan. 1, 1970 , measured in seconds. ... timer.c */ #include <stdio.h> #include <sys/types.h> #include <time.h> main() { int i; time_t t1,t2; (void) time(&t1); for (i=1;i<=300;++i) printf(``%d %d %d n'',i, i*i, i*i*i); (void) time(&t2); printf(`` n Time to do 300 squares and cubes= %d seconds n'', (int) t2-t1); } . ...

... Bad Astronomy . ... I think I will break from my usual format of Bad Astronomy/ Good Astronomy by saying that the way we define seasons currently is not strictly bad, but I feel (in my opinion!) that it could be better. The definition of when the seasons begin is at the moment of solstice or eq