As  it  has gotten longer since that nice-neighbourhood  pathway   initially
opened,   my  refuge  has become  busier  and buser.    While  the  nebulous
construction   fence reclaimed  silence  for a while, those not willing   to
creatively  jump their way by have mainly found that a few blocks deeper  in
there  is another path that links up.  The plethora  of dogwalkers  are very
genteel   but  I  am  not  particularly   after  passing   pedestrian    dog
conversations.  The edges of one mown section fringes into occasional  fairy
paths through the surrounding layer of Tradescantia  luring incautious  feet
into the swamp beneath. One of these paths is wholly dry, except where trees
have fallen  on or slid through it. Occasional  human and dog prints  affirm
the way.  About 50 metres on there is 5 metres of clear sand/silt  riverside
beach, riven by a tiny rivulet  down from 6 metres of cliff.   The odd shape
and scant primary succession  imply a treefall into the river.
Excuse   me, I do go on.  This week has been both busy and unfulfilling.   I
itinerantly  teach  in some small way. Lately I have been getting university
alumni to migrate from Notepad++ on Microsoft  Windows to Emacs orgmode on a
liferaft.    The university  and town are absolutely  owned by the Microsoft
sales rep except for an oily sheen of Google acquisitions.  People that find
me come with a sense of being born behind  enemy lines.
Enjoining  people  to orgmode  is against  my personal  current.   A hulking
monolith of writing, publishing, scheduling, tabulation, inline rendering of
images and TeX ensconsing the tangle and weave of code. I wonder if Knuth is
for or against this particular  progeny of his.
What I had been planning to scribble on in this resounding  new code silence
from me was constructive solid geometry (CSG). Since I first came upon it in
the context of electromagnetic  finite element analysis, I largely inherited
Gmsh. Gmsh sits preferentially  upon oce, being the lgpl product bait of yet
another  cad software  company.   I like that Gmsh furnishes  a light  C api
rather  than miring you in C++ idioms (cf cgal and its boost corollary).  It
is hard  to say what  the best choice of CSG is. There  are a handful  of 3D
programs   and  their libraries  that are GPL3+ rather  than the  commercial
enticement   LGPL.   Counter  to that is the temptation  to - since  I  know
particular  algorithms  and standard approaches  - just defpackage  myself a
little  lisp rather than introducing  a hard dependency on ECL's sffi. These
packages are the life's work of their major contributors though.  Eventually
I will settle down but for now I am a stone doomed to rolling.
Pivoting  a second  time I deeply  enjoyed  Boris Shminke's  post about deep
learning   automated  proofs.  Deep learning  success story articles   often
present  proofs of the nature and destination  of their convergence,   those
being  the controversial  bits of deep learning*.   Deep learning  converges
somewhere, eventually, and for any particular destination  there is a way to
converge  there, but whether the place you got and time it took to get there
was really that great can be dubious.
*I think.   I would  like to pre-defer  to Boris  on the issue.   I am  from
classical   machine   learning  around  receiver  operating   characteristic
statistics for foreground segmentation algorithms (slightly tongue in cheek,
what this means  is that you come up with a completely  arbitrary  algorithm
then search for / invent a new receiver operating characteristic metric that
happens to make whatever your algorithm  was look good. Two of my favourites
from about  10 years  ago were a Chinese research  group  who proposed  some
metric they didn't settle on, but tried something  like standard ROC metrics
within subsequent  dilations of gold standard foreground  segmentations  and
counting how the results changed.  Less tantilizingly, I saw an article that
claimed  to have the highest true positive fraction foreground  segmentation
ever recorded!  Despite its miserable false positive fraction.  (If you just
say 'true' no matter what your input was you can achieve this)).