Tiling, Osotua, and Recursing Profilers

Today I learned:

1) All possible triangles and quadrilaterals can perfectly tile a plane (that is, they can cover it perfectly without overlaps or gaps). No convex polygon with seven or more sides can tile a plane. The really interesting ones are pentagons and hexagons — there are proven to be exactly three hexagons capable of tiling a plane, and something like plane-tiling 30 pentagons that have been slowly discovered over the last 100 years (one by an amateur, middle-aged housewife who read about the problem in Scientific American).

2) There is a concept used in many East African tribes/cultures called osotua, which translates literally to “umbilical cord”, which describes a certain kind of gift-giving relationship between two people or families. Osotua is established between two people when one asks the other for a gift out of need — imminent starvation, for instance. The gift-asker must only ask for what he truly needs, and the gift-giver may, if he freely chooses, give the asker what he needs.

Once osotua is established, it doesn’t go away. There is no time limit on it, no condition under which it may be broken, no way it can be said to be “paid off” by either party. If one party of the osotua dies, it generally passes to that person’s family (I have no idea how they keep track of all of the osotuas going around).

Two people in osotua can, if they are in need, ask each other for gifts. Again, the gift-asking is limited to what is needed by the asker, but now the gift-giving person is essentially obligated to give whatever the asker needs. Sometimes this relationship is reciprocal, with both parties asking and giving in equal measures. Sometimes it is quite one-sided, with either the original asker or the original giver doing most of the asking.

3) (‪#‎python‬) You can profile cProfile! Just do "cProfile.run("cProfile.run('<your code here>')")" (mind the different quotation types).

I'm not sure why you'd ever want to do this, but you can.

‪#‎todayilearned‬