Builds a list of mathematicians from MacTutor index.
This list is sorted by link count (link count of a mathematician
is the number of links pointing from other mathematicians' pages
to the page of that mathematician).

Executed once 2019-10-21 and 22
to build an eminence indicator for an other program :
https://github.com/tig12/gauquelin5

Code released under the General Public Licence (GPL)
Written in PHP 7.2; tested on Linux Ubuntu 18.4

------------

Departure URL :
https://www-history.mcs.st-andrews.ac.uk/Indexes/Full_Chron.html

Result :
https://larzac.info/gauquelin5/eminence/mathematicians/mactutor-by-links.csv
See details of this file below


Installation
------------
Install PECL extension php-yaml :
sudo apt install php-yaml


Preparation
------------
- Copy config.yml.dist to config.yml
- Adapt the paths to your local machine


Execution
------------
In a console, from current directory (containing this README) :

Retrieve pages containing the biographies on your local machine :
php run/1-get-bios.php

Retrieve pages containing the places on your local machine :
php run/2-get-places.php

Generate csv :
php run/3-bylinks-csv.php


Execution result :
------------

step 1
permits to retrieve 2842 persons

step 2
permits to retrieve birthplaces except for 166 mathematicians
(1269 birthplaces)

step 3
see build/stats.php


Examine result
------------
php build/stats.php


Result
------------
https://larzac.info/gauquelin5/eminence/mathematicians/mactutor-by-links.csv
To open the resulting csv file, use ";" as separator. Do not use "," because some fields contain comas.

ID      : MacTutor id
NAME    : full name, as written in MacTutor site
N_LINKS : number of links pointing to a mathematician's page (link count).
B_DATE  : birth date, YYYY-MM-DD
B_PLACE : birth place, as written in MacTutor site
B_LG    : longitude of birth place, in decimal degrees
B_LAT   : latitude of birth place, in decimal degrees
B_WIKIPEDIA : Wikipedia url corresponding to birth place
D_DATE  : death date, YYYY-MM-DD
D_PLACE : death place


TODO
------------
- Possibility to retrieve wikipedia url from birth place => compute geonames id + country without ambiguity

- Handle "now" in MacTutor place names : possible to compute original place name and present place name


BUGS
------------
Cannot get coordinates for Sharnbrook.html
Cannot get coordinates for Wootton.html
Cannot get coordinates for Stepps.html
Cannot get coordinates for Shefong.html
Cannot get coordinates for Stockbridge.html
Cannot get coordinates for Obu.html
Cannot get coordinates for Guadalajara.html
Cannot get coordinates for Puzhou.html
Cannot get coordinates for New_Castle.html
Cannot get coordinates for Antinoupolis.html
Cannot get coordinates for Gifu.html
Cannot get coordinates for Kisai.html
Cannot get coordinates for Marosvasarhely.html
Cannot get coordinates for Lewisville.html
Cannot get coordinates for Donglai.html