anchor.diff:  "WC1R","530700","181700","51.51860","-0.11604","Camden Town","Greater London","ENG","England"
   "WC1V","530500","181500","51.51685","-0.11899","Camden Town","Greater London","ENG","England"
   "WC1X","530700","182400","51.52489","-0.11578","Camden Town","Greater London","ENG","England"
  -"WC2","530200","181100","51.51332","-0.12346","Westminster","London","ENG","England"
  +"WC2","530200","181100","51.51332","-0.12346",,"Westminster","ENG","England"
   "WC2A","530800","181400","51.51588","-0.11471","Camden Town","Greater London","ENG","England"
  -"WC2B","530300","181300","51.51510","-0.12195","Westminster","London","ENG","England"
  -"WC2E","530200","181000","51.51242","-0.12350","Westminster","London","ENG","England"
  +"WC2B","530300","181300","51.51510","-0.12195",,"Westminster","ENG","England"
  +"WC2E","530200","181000","51.51242","-0.12350",,"Westminster","ENG","England"
   "WC2H","529900","181100","51.51339","-0.12778","Camden Town","Greater London","ENG","England"
  -"WC2N","530100","180700","51.50975","-0.12505","Westminster","London","ENG","England"
  -"WC2R","530500","180900","51.51145","-0.11921","Westminster","London","ENG","England"
  +"WC2N","530100","180700","51.50975","-0.12505",,"Westminster","ENG","England"
  +"WC2R","530500","180900","51.51145","-0.11921",,"Westminster","ENG","England"
   "WD1","510700","195500","51.64692","-0.39984","Watford","Hertfordshire","ENG","England"
   "WD17","510300","197100","51.66138","-0.40512","Watford","Hertfordshire","ENG","England"
   "WD18","509700","195600","51.64801","-0.41426","Watford","Hertfordshire","ENG","England"
  
positive.code: "SW17","527700","171800","51.43030","-0.16283","Wandsworth","Greater London","ENG","England"
  "SW18","525800","173900","51.44960","-0.18941","Wandsworth","Greater London","ENG","England"
  "SW19","524900","170900","51.42284","-0.20341","Merton","Greater London","ENG","England"
  "SW1A","529700","179900","51.50265","-0.13111","Westminster","London","ENG","England"
  "SW1E","529200","179300","51.49737","-0.13853","Westminster","London","ENG","England"
  "SW1H","529600","179400","51.49818","-0.13273","Westminster","London","ENG","England"
  "SW1P","529600","179100","51.49548","-0.13284","Westminster","London","ENG","England"
  "SW1V","529300","178500","51.49016","-0.13738","Westminster","London","ENG","England"
  "SW1W","528600","178800","51.49302","-0.14735","Westminster","London","ENG","England"
  "SW1X","528200","179300","51.49760","-0.15293","Westminster","London","ENG","England"
  "SW1Y","529500","180200","51.50539","-0.13388","Westminster","London","ENG","England"
  "SW2","530700","174000","51.44939","-0.11889","Lambeth","Greater London","ENG","England"
  "SW20","523400","169500","51.41058","-0.22547","Merton","Greater London","ENG","England"
  "SW3","527400","178400","51.48969","-0.16477","Kensington","Greater London","ENG","England"
  
negative.code: "PH40","169900","792200","56.96381","-5.78560",,"Highland","SCT","Scotland"
  "PH41","167300","796800","57.00374","-5.83251","Mallaig","Highland","SCT","Scotland"
  "PH42","147900","786600","56.90217","-6.14094","Isle Of Eigg","Highland","SCT","Scotland"
  "PH43","140200","799700","57.01529","-6.28049","Isle Of Rum","Highland","SCT","Scotland"
  "PH44","127000","805200","57.05693","-6.50319","Isle Of Canna","Highland","SCT","Scotland"
  "PH49","209500","758000","56.67500","-5.10977","Glencoe","Highland","SCT","Scotland"
  "PH5","287000","716700","56.32927","-3.82770","Muthill","Perth and Kinross","SCT","Scotland"
  