annotate org/types.org @ 4:a227fe337e83

fixed headers
author Robert McIntyre <rlm@mit.edu>
date Thu, 20 Oct 2011 01:12:46 -0700
parents 55bba4805393
children ff9655688ddb
rev   line source
rlm@0 1 #+TITLE: Breadth-first Search for Effective Pokemon Types
rlm@0 2 #+AUTHOR: Robert McIntyre & Dylan Holmes
rlm@0 3 #+EMAIL: rlm@mit.edu
rlm@4 4 #+SETUPFILE: ../../aurellem/org/setup.org
rlm@4 5 #+INCLUDE: ../../aurellem/org/level-0.org
rlm@0 6
rlm@0 7 * The Pok\eacute{}mon Type System
rlm@0 8
rlm@0 9 The Pok\eacute{}mon type system consists of seventeen different
rlm@0 10 \ldquo{}types\rdquo{} (Rock, Grass, Ice, Psychic, Ground, Bug, Flying,
rlm@0 11 Fire, Fighting, Dark, Dragon, Poison, Water, Ghost, Normal, Electric,
rlm@0 12 and Steel) that interact like an extended version of
rlm@0 13 Rock-Paper-Scissors: for example, the Fire type is strong against the
rlm@0 14 Grass type but weak against the Water type. In the table below, we've
rlm@0 15 recorded the relative strengths of each of the types in the
rlm@0 16 Pok\eacute{}mon type system; the number in each cell indicates how
rlm@0 17 effective an attack of the type in the row is against a
rlm@0 18 Pok\eacute{}mon of the type in the column. We call these numbers
rlm@0 19 /susceptibilities/ because we are interested in the column totals,
rlm@0 20 which quantify the overall vulnerability of each Pok\eacute{}mon type
rlm@0 21 (as opposed to the row totals, which quantify the overall
rlm@0 22 effectiveness of each attack type.)
rlm@0 23
rlm@0 24 In the Pok\eacute{}mon games, only four susceptibility values (two,
rlm@0 25 one, one-half, and zero) occur. These numbers indicate particularly
rlm@0 26 high susceptibility, average susceptibility, particularly low
rlm@0 27 susceptibility, and no susceptibility
rlm@0 28 (immunity). Here is the entire Pok\eacute{}mon type chart.
rlm@0 29
rlm@0 30
rlm@0 31
rlm@0 32 ** TODO add the pokemon chart in a pretty form
rlm@0 33
rlm@0 34 * COMMENT Pokemon Table Data
rlm@0 35
rlm@0 36 #+caption: The rows are attack types, while the columns are defense types. To see the multiplier for a pokemon attack against a certain type, follow the row for the attack type to the column of the defending type.
rlm@0 37 #+label: pokemon-matchups
rlm@0 38 #+tblname: pokemon-table-gen-two
rlm@0 39 | | normal | fire | water | electric | grass | ice | fighting | poison | ground | flying | psychic | bug | rock | ghost | dragon | dark | steel |
rlm@0 40 |----------+--------+------+-------+----------+-------+-----+----------+--------+--------+--------+---------+-----+------+-------+--------+------+-------|
rlm@0 41 | normal | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | .5 | 0 | 1 | 1 | .5 |
rlm@0 42 | fire | 1 | .5 | .5 | 1 | 2 | 2 | 1 | 1 | 1 | 1 | 1 | 2 | .5 | 1 | .5 | 1 | 2 |
rlm@0 43 | water | 1 | 2 | .5 | 1 | .5 | 1 | 1 | 1 | 2 | 1 | 1 | 1 | 2 | 1 | .5 | 1 | 1 |
rlm@0 44 | electric | 1 | 1 | 2 | .5 | .5 | 1 | 1 | 1 | 0 | 2 | 1 | 1 | 1 | 1 | .5 | 1 | 1 |
rlm@0 45 | grass | 1 | .5 | 2 | 1 | .5 | 1 | 1 | .5 | 2 | .5 | 1 | .5 | 2 | 1 | .5 | 1 | .5 |
rlm@0 46 | ice | 1 | .5 | .5 | 1 | 2 | .5 | 1 | 1 | 2 | 2 | 1 | 1 | 1 | 1 | 2 | 1 | .5 |
rlm@0 47 | fighting | 2 | 1 | 1 | 1 | 1 | 2 | 1 | .5 | 1 | .5 | .5 | .5 | 2 | 0 | 1 | 2 | 2 |
rlm@0 48 | poison | 1 | 1 | 1 | 1 | 2 | 1 | 1 | .5 | .5 | 1 | 1 | 1 | .5 | .5 | 1 | 1 | 0 |
rlm@0 49 | ground | 1 | 2 | 1 | 2 | .5 | 1 | 1 | 2 | 1 | 0 | 1 | .5 | 2 | 1 | 1 | 1 | 2 |
rlm@0 50 | flying | 1 | 1 | 1 | .5 | 2 | 1 | 2 | 1 | 1 | 1 | 1 | 2 | .5 | 1 | 1 | 1 | .5 |
rlm@0 51 | psychic | 1 | 1 | 1 | 1 | 1 | 1 | 2 | 2 | 1 | 1 | .5 | 1 | 1 | 1 | 1 | 0 | .5 |
rlm@0 52 | bug | 1 | .5 | 1 | 1 | 2 | 1 | .5 | .5 | 1 | .5 | 2 | 1 | 1 | .5 | 1 | 2 | .5 |
rlm@0 53 | rock | 1 | 2 | 1 | 1 | 1 | 2 | .5 | 1 | .5 | 2 | 1 | 2 | 1 | 1 | 1 | 1 | .5 |
rlm@0 54 | ghost | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 2 | 1 | .5 | .5 |
rlm@0 55 | dragon | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 2 | 1 | .5 |
rlm@0 56 | dark | 1 | 1 | 1 | 1 | 1 | 1 | .5 | 1 | 1 | 1 | 2 | 1 | 1 | 2 | 1 | .5 | .5 |
rlm@0 57 | steel | 1 | .5 | .5 | .5 | 1 | 2 | 1 | 1 | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 1 | .5 |
rlm@0 58
rlm@0 59 #+caption: this is the old table from generation 1. The differences are: dark and ghost are missing, Bus is super against Poison, Poison is super against Bug, Bug is regularly effective against Ghost, and Ice is normally effective against Fire. Ghost is not effective against psychic.
rlm@0 60 #+label: pokemon-matchups-gen-1
rlm@0 61 #+tblname: pokemon-table-gen-one
rlm@0 62 | | normal | fire | water | electric | grass | ice | fighting | poison | ground | flying | psychic | bug | rock | ghost | dragon |
rlm@0 63 |----------+--------+------+-------+----------+-------+-----+----------+--------+--------+--------+---------+-----+------+-------+--------|
rlm@0 64 | normal | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | .5 | 0 | 1 |
rlm@0 65 | fire | 1 | .5 | .5 | 1 | 2 | 2 | 1 | 1 | 1 | 1 | 1 | 2 | .5 | 1 | .5 |
rlm@0 66 | water | 1 | 2 | .5 | 1 | .5 | 1 | 1 | 1 | 2 | 1 | 1 | 1 | 2 | 1 | .5 |
rlm@0 67 | electric | 1 | 1 | 2 | .5 | .5 | 1 | 1 | 1 | 0 | 2 | 1 | 1 | 1 | 1 | .5 |
rlm@0 68 | grass | 1 | .5 | 2 | 1 | .5 | 1 | 1 | .5 | 2 | .5 | 1 | .5 | 2 | 1 | .5 |
rlm@0 69 | ice | 1 | 1 | .5 | 1 | 2 | .5 | 1 | 1 | 2 | 2 | 1 | 1 | 1 | 1 | 2 |
rlm@0 70 | fighting | 2 | 1 | 1 | 1 | 1 | 2 | 1 | .5 | 1 | .5 | .5 | .5 | 2 | 0 | 1 |
rlm@0 71 | poison | 1 | 1 | 1 | 1 | 2 | 1 | 1 | .5 | .5 | 1 | 1 | 2 | .5 | .5 | 1 |
rlm@0 72 | ground | 1 | 2 | 1 | 2 | .5 | 1 | 1 | 2 | 1 | 0 | 1 | .5 | 2 | 1 | 1 |
rlm@0 73 | flying | 1 | 1 | 1 | .5 | 2 | 1 | 2 | 1 | 1 | 1 | 1 | 2 | .5 | 1 | 1 |
rlm@0 74 | psychic | 1 | 1 | 1 | 1 | 1 | 1 | 2 | 2 | 1 | 1 | .5 | 1 | 1 | 1 | 1 |
rlm@0 75 | bug | 1 | .5 | 1 | 1 | 2 | 1 | .5 | 2 | 1 | .5 | 2 | 1 | 1 | 0 | 1 |
rlm@0 76 | rock | 1 | 2 | 1 | 1 | 1 | 2 | .5 | 1 | .5 | 2 | 1 | 2 | 1 | 1 | 1 |
rlm@0 77 | ghost | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 2 | 1 |
rlm@0 78 | dragon | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 2 |
rlm@0 79
rlm@0 80 * Representing the Data
rlm@0 81
rlm@0 82 After creating the Pok\eacute{}mon types namespace, we store the table
rlm@0 83 of susceptibilities in =pokemon-table-gen-one= and
rlm@0 84 =pokemon-table-gen-two=, each of which is a simple vector of
rlm@0 85 vectors. Because a vector of vectors can be cumbersome, we do not
rlm@0 86 access the tables directly; instead, we use the derivative structures
rlm@0 87 =attack-strengths= and =defense-strengths=, which are functions which
rlm@0 88 return hash-maps associating each row (respectively column) of the
rlm@0 89 table with its corresponding Pok\eacute{}mon type.
rlm@0 90
rlm@0 91
rlm@0 92
rlm@0 93 #+srcname: header
rlm@0 94 #+begin_src clojure :results silent
rlm@0 95 (ns pokemon.types
rlm@0 96 (:use rlm.ns-rlm))
rlm@0 97 (rlm.ns-rlm/ns-clone rlm.light-base)
rlm@0 98 (use 'clojure.set)
rlm@0 99 #+end_src
rlm@0 100
rlm@0 101 #+srcname: data(pokemon-table-gen-one=pokemon-table-gen-one, pokemon-table-gen-two=pokemon-table-gen-two)
rlm@0 102 #+begin_src clojure :results silent
rlm@0 103 (in-ns 'pokemon.types)
rlm@0 104 ;; record type strengths as a vector of vectors
rlm@0 105 (def pokemon-gen-one pokemon-table-gen-one)
rlm@0 106 (def pokemon-gen-two pokemon-table-gen-two)
rlm@0 107
rlm@0 108 (defn type-names [] (vec (doall (map (comp keyword first) pokemon-gen-two))))
rlm@0 109
rlm@0 110 (defn attack-strengths []
rlm@0 111 (zipmap
rlm@0 112 (type-names)
rlm@0 113 (map (comp vec rest) pokemon-gen-two)))
rlm@0 114
rlm@0 115 (defn defense-strengths []
rlm@0 116 (zipmap (type-names)
rlm@0 117 (map
rlm@0 118 (apply juxt (map (attack-strengths) (type-names)))
rlm@0 119 (range (count (type-names))))))
rlm@0 120 #+end_src
rlm@0 121
rlm@0 122 #+begin_src clojure :results output :exports both
rlm@0 123 (clojure.pprint/pprint pokemon.types/pokemon-gen-two)
rlm@0 124 #+end_src
rlm@0 125
rlm@0 126 #+results:
rlm@0 127 #+begin_example
rlm@0 128 (("normal" 1 1 1 1 1 1 1 1 1 1 1 1 0.5 0 1 1 0.5)
rlm@0 129 ("fire" 1 0.5 0.5 1 2 2 1 1 1 1 1 2 0.5 1 0.5 1 2)
rlm@0 130 ("water" 1 2 0.5 1 0.5 1 1 1 2 1 1 1 2 1 0.5 1 1)
rlm@0 131 ("electric" 1 1 2 0.5 0.5 1 1 1 0 2 1 1 1 1 0.5 1 1)
rlm@0 132 ("grass" 1 0.5 2 1 0.5 1 1 0.5 2 0.5 1 0.5 2 1 0.5 1 0.5)
rlm@0 133 ("ice" 1 0.5 0.5 1 2 0.5 1 1 2 2 1 1 1 1 2 1 0.5)
rlm@0 134 ("fighting" 2 1 1 1 1 2 1 0.5 1 0.5 0.5 0.5 2 0 1 2 2)
rlm@0 135 ("poison" 1 1 1 1 2 1 1 0.5 0.5 1 1 1 0.5 0.5 1 1 0)
rlm@0 136 ("ground" 1 2 1 2 0.5 1 1 2 1 0 1 0.5 2 1 1 1 2)
rlm@0 137 ("flying" 1 1 1 0.5 2 1 2 1 1 1 1 2 0.5 1 1 1 0.5)
rlm@0 138 ("psychic" 1 1 1 1 1 1 2 2 1 1 0.5 1 1 1 1 0 0.5)
rlm@0 139 ("bug" 1 0.5 1 1 2 1 0.5 0.5 1 0.5 2 1 1 0.5 1 2 0.5)
rlm@0 140 ("rock" 1 2 1 1 1 2 0.5 1 0.5 2 1 2 1 1 1 1 0.5)
rlm@0 141 ("ghost" 0 1 1 1 1 1 1 1 1 1 2 1 1 2 1 0.5 0.5)
rlm@0 142 ("dragon" 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 1 0.5)
rlm@0 143 ("dark" 1 1 1 1 1 1 0.5 1 1 1 2 1 1 2 1 0.5 0.5)
rlm@0 144 ("steel" 1 0.5 0.5 0.5 1 2 1 1 1 1 1 1 2 1 1 1 0.5))
rlm@0 145 #+end_example
rlm@0 146
rlm@0 147 =pokemon-gen-two= is a simple list-of-list data structure.
rlm@0 148
rlm@0 149 #+begin_src clojure :results output :exports both
rlm@0 150 (clojure.pprint/pprint (pokemon.types/defense-strengths))
rlm@0 151 #+end_src
rlm@0 152
rlm@0 153 #+results:
rlm@0 154 #+begin_example
rlm@0 155 {:water [1 0.5 0.5 2 2 0.5 1 1 1 1 1 1 1 1 1 1 0.5],
rlm@0 156 :psychic [1 1 1 1 1 1 0.5 1 1 1 0.5 2 1 2 1 2 1],
rlm@0 157 :dragon [1 0.5 0.5 0.5 0.5 2 1 1 1 1 1 1 1 1 2 1 1],
rlm@0 158 :fire [1 0.5 2 1 0.5 0.5 1 1 2 1 1 0.5 2 1 1 1 0.5],
rlm@0 159 :ice [1 2 1 1 1 0.5 2 1 1 1 1 1 2 1 1 1 2],
rlm@0 160 :grass [1 2 0.5 0.5 0.5 2 1 2 0.5 2 1 2 1 1 1 1 1],
rlm@0 161 :ghost [0 1 1 1 1 1 0 0.5 1 1 1 0.5 1 2 1 2 1],
rlm@0 162 :poison [1 1 1 1 0.5 1 0.5 0.5 2 1 2 0.5 1 1 1 1 1],
rlm@0 163 :flying [1 1 1 2 0.5 2 0.5 1 0 1 1 0.5 2 1 1 1 1],
rlm@0 164 :normal [1 1 1 1 1 1 2 1 1 1 1 1 1 0 1 1 1],
rlm@0 165 :rock [0.5 0.5 2 1 2 1 2 0.5 2 0.5 1 1 1 1 1 1 2],
rlm@0 166 :electric [1 1 1 0.5 1 1 1 1 2 0.5 1 1 1 1 1 1 0.5],
rlm@0 167 :ground [1 1 2 0 2 2 1 0.5 1 1 1 1 0.5 1 1 1 1],
rlm@0 168 :fighting [1 1 1 1 1 1 1 1 1 2 2 0.5 0.5 1 1 0.5 1],
rlm@0 169 :dark [1 1 1 1 1 1 2 1 1 1 0 2 1 0.5 1 0.5 1],
rlm@0 170 :steel [0.5 2 1 1 0.5 0.5 2 0 2 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5],
rlm@0 171 :bug [1 2 1 1 0.5 1 0.5 1 0.5 2 1 1 2 1 1 1 1]}
rlm@0 172 #+end_example
rlm@0 173
rlm@0 174 =defense-strengths= is a more convenient form of =pokemon-gen-two=, with key/value pair access.
rlm@0 175
rlm@0 176 * Interfacing with the Data
rlm@0 177 #+srcname: types
rlm@0 178 #+begin_src clojure :results silent
rlm@0 179 (in-ns 'pokemon.types)
rlm@0 180
rlm@0 181 (defn multitypes "All combinations of up to n types" [n]
rlm@0 182 (vec
rlm@0 183 (map vec
rlm@0 184 (reduce concat
rlm@0 185 (map (partial combinations (type-names))
rlm@0 186 (range 1 (inc n)))))))
rlm@0 187
rlm@0 188 (defn susceptibility ;; susceptibility-map
rlm@0 189 "Hash-map of the susceptibilities of the given type combination
rlm@0 190 to each type of attack"
rlm@0 191 [pkmn-types]
rlm@0 192 (rlm.map-utils/map-vals
rlm@0 193 clojure.core/rationalize
rlm@0 194 (apply hash-map
rlm@0 195 (interleave (type-names)
rlm@0 196 (apply (partial map *)
rlm@0 197 (map (defense-strengths) pkmn-types))))))
rlm@0 198
rlm@0 199 (defn susceptance ;; susceptibility
rlm@0 200 "The cumulative susceptibility of the given type combination"
rlm@0 201 [types]
rlm@0 202 (reduce + (map sqr (vals (susceptibility types)))))
rlm@0 203 #+end_src
rlm@0 204
rlm@0 205 * Best-First Search
rlm@0 206
rlm@0 207 I'd like to find type combinations that are interesting, but the total
rlm@0 208 number of combinations gets huge as we begin to consider more
rlm@0 209 types. For example, the total possible number of type combinations
rlm@0 210 given just 8 possible types is: 17^{8} = 6975757441 combinations.
rlm@0 211 Therefore, it's prudent to use search.
rlm@0 212
rlm@0 213 These functions are a simple implementation of best-first search in
rlm@0 214 clojure. The idea to start off with a collection of nodes and some way
rlm@0 215 of finding the best node, and to always expand the best node at every
rlm@0 216 step.
rlm@0 217
rlm@0 218 #+srcname: search
rlm@0 219 #+begin_src clojure :results silent
rlm@0 220 (in-ns 'pokemon.types)
rlm@0 221
rlm@0 222 (defn comparatize
rlm@0 223 "Define a comparator which uses the numerical outputs of fn as its criterion.
rlm@0 224 Objects are sorted in increasing numerical order. Objects with the same fn-value
rlm@0 225 are further compared by clojure.core/compare."
rlm@0 226 [fun]
rlm@0 227 (fn [a b]
rlm@0 228 (let [val-a (fun a)
rlm@0 229 val-b (fun b)]
rlm@0 230 (cond
rlm@0 231 ;; if the function cannot differentiate the two values
rlm@0 232 ;; then compare the two values using clojure.core/compare
rlm@0 233 (= val-a val-b) (compare a b)
rlm@0 234 true
rlm@0 235 ;; LOWER values of the function are preferred
rlm@0 236 (compare (- val-a val-b) 0)))))
rlm@0 237
rlm@0 238 (defn-memo best-first-step [successors [visited unvisited]]
rlm@0 239 (cond (empty? unvisited) nil
rlm@0 240 true
rlm@0 241 (let [best-node (first unvisited)
rlm@0 242 visited* (conj visited best-node)
rlm@0 243 unvisited*
rlm@0 244 (difference
rlm@0 245 (union unvisited (set (successors best-node)))
rlm@0 246 visited*)]
rlm@0 247 (println best-node)
rlm@0 248 [visited* unvisited*])))
rlm@0 249
rlm@0 250 ;; memoize partial from core so that for example
rlm@0 251 ;; (= (partial + 1) (partial + 1))
rlm@0 252 ;; this way, best first search can take advantage of the memoization
rlm@0 253 ;; of best-first step
rlm@0 254 (undef partial)
rlm@0 255 (def partial (memoize clojure.core/partial))
rlm@0 256
rlm@0 257 (defn best-first-search
rlm@0 258 "Searches through a network of alternatives, pursuing
rlm@0 259 initially-promising positions first. Comparator defines which
rlm@0 260 positions are more promising, successors produces a list of improved
rlm@0 261 positions from the given position (if any exist), and initial-nodes is
rlm@0 262 a list of starting positions. Returns a lazy sequence of search results
rlm@0 263 [visited-nodes unvisited-nodes], which terminates when
rlm@0 264 there are no remaining unvisited positions."
rlm@0 265 [comparator successors initial-nodes]
rlm@0 266 (let [initial-nodes
rlm@0 267 (apply (partial sorted-set-by comparator) initial-nodes)
rlm@0 268 initial-visited-nodes (sorted-set-by comparator)
rlm@0 269 step (partial best-first-step successors)]
rlm@0 270 (take-while
rlm@0 271 (comp not nil?)
rlm@0 272 (iterate step [initial-visited-nodes initial-nodes]))))
rlm@0 273
rlm@0 274 #+end_src
rlm@0 275
rlm@0 276
rlm@0 277 Now that we have a basic best-first-search, it's convenient to write a
rlm@0 278 few pokemon-type specific convenience functions.
rlm@0 279
rlm@0 280 #+srcname: pokemon-search
rlm@0 281 #+begin_src clojure :results silent
rlm@0 282 (in-ns 'pokemon.types)
rlm@0 283 (defvar type-compare (comparatize susceptance)
rlm@0 284 "compare two type combinations wrt their susceptibilities")
rlm@0 285
rlm@0 286 (defn type-successors
rlm@0 287 "Return the set of types that can be made by appending a single type
rlm@0 288 to the given combination."
rlm@0 289 [type]
rlm@0 290 (if (nil? type) '()
rlm@0 291 (set (map (comp vec sort (partial into type)) (multitypes 1)))))
rlm@0 292
rlm@0 293 (defn immortal?
rlm@0 294 "A type combo is immortal if it is resistant or invulnerable to
rlm@0 295 every pokemon type. This is because that set of types can just be
rlm@0 296 repeated to achieve as low a susceptance as desired"
rlm@0 297 [type]
rlm@0 298 (every? (partial > 1) (vals (susceptibility type))))
rlm@0 299
rlm@0 300 (defn type-successors*
rlm@0 301 "Stop expanding a type if it's immortal, or if it is longer than or
rlm@0 302 equal to limit-size. Also, only return type additions that are
rlm@0 303 strictly better than the initial type."
rlm@0 304 [limit-size type]
rlm@0 305 (if (or (<= limit-size (count type)) (immortal? type)) '()
rlm@0 306 (set (filter #(< 0 (type-compare type %)) (type-successors type)))))
rlm@0 307
rlm@0 308 (defn pokemon-type-search
rlm@0 309 "Search among type-combos no greater than length n, limited by limit
rlm@0 310 steps of best-first-search."
rlm@0 311 ([n] (pokemon-type-search n Integer/MAX_VALUE))
rlm@0 312 ([n limit]
rlm@0 313 (first (last
rlm@0 314 (take
rlm@0 315 limit
rlm@0 316 (best-first-search
rlm@0 317 type-compare
rlm@0 318 (partial type-successors* n)
rlm@0 319 (multitypes 1)))))))
rlm@0 320
rlm@0 321 (defvar immortals
rlm@0 322 (comp (partial filter immortal?) pokemon-type-search)
rlm@0 323 "find all the immortal pokemon types ")
rlm@0 324
rlm@0 325 #+end_src
rlm@0 326
rlm@0 327 Because there are so many type combinations, it's important to narrow
rlm@0 328 down the results as much as possible. That is why =type-successors*=
rlm@0 329 only returns types that are actually better than the type it is given.
rlm@0 330
rlm@0 331 Best-first search can get caught optimizing a single type forever, so
rlm@0 332 it's also important to limit the search space to be finite by setting
rlm@0 333 an upper bound on the length of a type combo.
rlm@0 334
rlm@0 335 * Results
rlm@0 336 ** The best dual-type combo
rlm@0 337
rlm@0 338 #+begin_src clojure :results cache verbatim :exports both
rlm@0 339 (first (pokemon.types/pokemon-type-search 2))
rlm@0 340 #+end_src
rlm@0 341
rlm@0 342 #+results:
rlm@0 343 : [:dark :ghost]
rlm@0 344
rlm@0 345 Dark and Ghost, which additionally has the property of having no
rlm@0 346 weaknesses to any other type, is the best type combo in terms of
rlm@0 347 susceptance.
rlm@0 348
rlm@0 349 The Dark and Steel types were introduced many years after
rlm@0 350 pok\eacute{}mon started. In addition to the additional types, the
rlm@0 351 pok\eacute{}mon games gained a few new rules concerning some of the
rlm@0 352 matchups of the original types. Therefore, it's also interesting to see what
rlm@0 353 type combination was most powerful before those types and new rules were introduced.
rlm@0 354
rlm@0 355 The easiest way to do this with my setup is to just rebind the
rlm@0 356 =pokemon-gen-two= table to the =pokemon-gen-one= table. Since
rlm@0 357 everything that references this variable is a function and we're not
rlm@0 358 doing anything too crazy with lazy-sequences and late-binding, this
rlm@0 359 simple macro will do the job.
rlm@0 360
rlm@0 361 #+srcname: old-school
rlm@0 362 #+begin_src clojure :results silent
rlm@0 363 (in-ns 'pokemon.types)
rlm@0 364
rlm@0 365 (defmacro old-school
rlm@0 366 [& forms]
rlm@0 367 `(binding [pokemon-gen-two pokemon-gen-one] ~@forms))
rlm@0 368 #+end_src
rlm@0 369
rlm@0 370 Using the =old-school= macro, it's easy to find answers for the
rlm@0 371 original 15 pokemon types as well as the expanded pokemon types
rlm@0 372 introduced later.
rlm@0 373
rlm@0 374 #+begin_src clojure :results verbatim :exports both :cache yes
rlm@0 375 (pokemon.types/old-school (first (pokemon.types/pokemon-type-search 2)))
rlm@0 376 #+end_src
rlm@0 377
rlm@0 378 #+results[f43470fdf460ed546e9c57879abc9eda56da129f]:
rlm@0 379 : [:ghost :psychic]
rlm@0 380
rlm@0 381 Ghost and Psychic also manages to have no weaknesses to any of the original
rlm@0 382 types.
rlm@0 383
rlm@0 384 #+begin_src clojure :results output :exports both
rlm@0 385 (clojure.pprint/pprint
rlm@0 386 (pokemon.types/old-school
rlm@0 387 (pokemon.types/susceptibility [:ghost :psychic])))
rlm@0 388 #+end_src
rlm@0 389
rlm@0 390 #+results:
rlm@0 391 #+begin_example
rlm@0 392 {:water 1,
rlm@0 393 :psychic 1/2,
rlm@0 394 :dragon 1,
rlm@0 395 :fire 1,
rlm@0 396 :ice 1,
rlm@0 397 :grass 1,
rlm@0 398 :ghost 0,
rlm@0 399 :poison 1/2,
rlm@0 400 :flying 1,
rlm@0 401 :normal 0,
rlm@0 402 :rock 1,
rlm@0 403 :electric 1,
rlm@0 404 :ground 1,
rlm@0 405 :fighting 0,
rlm@0 406 :bug 0}
rlm@0 407 #+end_example
rlm@0 408
rlm@0 409 ** An Immortal Type
rlm@0 410 It's possible to quickly find an immortal type by giving the search
rlm@0 411 a long enough maximum type length. 50 rounds of search with a max
rlm@0 412 type limit of 10 is enough to find an immortal type.
rlm@0 413
rlm@0 414 #+begin_src clojure :results scalar :exports both
rlm@0 415 (first (pokemon.types/pokemon-type-search 10 50))
rlm@0 416 #+end_src
rlm@0 417
rlm@0 418 #+results:
rlm@0 419 : [:dragon :fire :flying :ghost :grass :ground :steel :steel :water :water]
rlm@0 420
rlm@0 421
rlm@0 422 #+begin_src clojure :results output :exports both
rlm@0 423 (clojure.pprint/pprint
rlm@0 424 (pokemon.types/susceptibility
rlm@0 425 [:dragon :fire :flying :ghost :grass :ground :steel :steel :water :water]))
rlm@0 426 #+end_src
rlm@0 427
rlm@0 428 #+results:
rlm@0 429 #+begin_example
rlm@0 430 {:water 1/4,
rlm@0 431 :psychic 1/4,
rlm@0 432 :dragon 1/2,
rlm@0 433 :fire 1/2,
rlm@0 434 :ice 1/2,
rlm@0 435 :grass 1/8,
rlm@0 436 :ghost 1/2,
rlm@0 437 :poison 0,
rlm@0 438 :flying 1/2,
rlm@0 439 :normal 0,
rlm@0 440 :rock 1/2,
rlm@0 441 :electric 0,
rlm@0 442 :ground 0,
rlm@0 443 :fighting 0,
rlm@0 444 :dark 1/2,
rlm@0 445 :steel 1/32,
rlm@0 446 :bug 1/16}
rlm@0 447 #+end_example
rlm@0 448
rlm@0 449 ** Explanations for Common Pok\eacute{}mon Strategies
rlm@0 450
rlm@0 451 Many people start out a battle with either a normal pok\eacute{}mon or an
rlm@0 452 electric pok\eacute{}mon, and here's some justification for that choice.
rlm@0 453
rlm@0 454 #+srcname: weaknesses
rlm@0 455 #+begin_src clojure :results silent
rlm@0 456 (in-ns 'pokemon.types)
rlm@0 457 (defn critical-weaknesses [type]
rlm@0 458 (count (filter #(> % 1) (vals (susceptibility type)))))
rlm@0 459 #+end_src
rlm@0 460
rlm@0 461 #+begin_src clojure :exports both :results output
rlm@0 462 (clojure.pprint/pprint
rlm@0 463 (sort-by pokemon.types/critical-weaknesses (pokemon.types/multitypes 1)))
rlm@0 464 #+end_src
rlm@0 465
rlm@0 466 #+results:
rlm@0 467 #+begin_example
rlm@0 468 ([:normal]
rlm@0 469 [:electric]
rlm@0 470 [:water]
rlm@0 471 [:fighting]
rlm@0 472 [:poison]
rlm@0 473 [:ghost]
rlm@0 474 [:dragon]
rlm@0 475 [:dark]
rlm@0 476 [:fire]
rlm@0 477 [:ground]
rlm@0 478 [:flying]
rlm@0 479 [:psychic]
rlm@0 480 [:bug]
rlm@0 481 [:steel]
rlm@0 482 [:ice]
rlm@0 483 [:grass]
rlm@0 484 [:rock])
rlm@0 485 #+end_example
rlm@0 486
rlm@0 487 Electric and Normal are among the best types with which to start the
rlm@0 488 game, since they have the fewest weaknesses among all the types.
rlm@0 489
rlm@0 490 At the beginning of the pok\eacute{}mon games, players are given a choice
rlm@0 491 between the Fire pok\eacute{}mon Charmander, the Water pok\eacute{}mon Squirtle, or
rlm@0 492 the Grass/Poison pok\eacute{}mon Bulbasaur.
rlm@0 493
rlm@0 494 #+begin_src clojure :exports both :results verbatim
rlm@0 495 (sort-by pokemon.types/susceptance [[:fire] [:water] [:grass :poison]])
rlm@0 496 #+end_src
rlm@0 497
rlm@0 498 #+results:
rlm@0 499 : ([:water] [:fire] [:grass :poison])
rlm@0 500
rlm@0 501 As can be seen, the Water pok\eacute{}mon Squirtle is the most solid
rlm@0 502 choice starting out, insofar as susceptance is concerned.
rlm@0 503
rlm@0 504 ** The Worst Pok\eacute{}mon Types
rlm@0 505
rlm@0 506 #+srcname: weak-types
rlm@0 507 #+begin_src clojure :results silent
rlm@0 508 (in-ns 'pokemon.types)
rlm@0 509
rlm@0 510 (defn type-compare-weak
rlm@0 511 "compare first by total number of critical-weaknesses,
rlm@0 512 then by overall susceptance, favoring weaker types."
rlm@0 513 [type-1 type-2]
rlm@0 514 (let [measure (memoize (juxt critical-weaknesses susceptance))]
rlm@0 515 (if (= (measure type-2) (measure type-1))
rlm@0 516 (compare type-2 type-1)
rlm@0 517 (compare (measure type-2) (measure type-1)))))
rlm@0 518
rlm@0 519 (defn resistant?
rlm@0 520 "might as well get rid of types that are resistant to any type"
rlm@0 521 [type]
rlm@0 522 (not (every? #(< 0 %) (vals (susceptibility type)))))
rlm@0 523
rlm@0 524 (defn type-successors-weak
rlm@0 525 [limit type]
rlm@0 526 (set (if (<= limit (count type)) '()
rlm@0 527 (filter #(< 0 (type-compare-weak type %))
rlm@0 528 (remove resistant? (type-successors type))))))
rlm@0 529
rlm@0 530 (defn pokemon-type-search-weak
rlm@0 531 "Search among type-combos no greater than length n, limited by limit
rlm@0 532 steps of best-first-search."
rlm@0 533 ([n] (pokemon-type-search-weak n Integer/MAX_VALUE))
rlm@0 534 ([n limit]
rlm@0 535 (first (last
rlm@0 536 (take
rlm@0 537 limit
rlm@0 538 (best-first-search
rlm@0 539 type-compare-weak
rlm@0 540 (partial type-successors-weak n)
rlm@0 541 (multitypes 1)))))))
rlm@0 542 #+end_src
rlm@0 543
rlm@0 544
rlm@0 545 #+begin_src clojure :results scalar :exports both
rlm@0 546 (first (pokemon.types/pokemon-type-search-weak 1))
rlm@0 547 #+end_src
rlm@0 548
rlm@0 549 #+results:
rlm@0 550 : [:rock]
rlm@0 551
rlm@0 552 Poor Rock. It's just not that good a type. Maybe this is why Brock
rlm@0 553 (who has rock pok\eacute{}mon) is the first gym leader in the games.
rlm@0 554
rlm@0 555 #+begin_src clojure :results scalar cache :exports both
rlm@0 556 (first (pokemon.types/pokemon-type-search-weak 2))
rlm@0 557 #+end_src
rlm@0 558
rlm@0 559 #+results:
rlm@0 560 : [:grass :ice]
rlm@0 561
rlm@0 562 # ;;bonus convergently immortal type combo
rlm@0 563 # (susceptance (vec (concat (repeat 150 :water) (repeat 50 :poison) (repeat 50 :steel) [:ghost :normal :flying :ground :dark])))
rlm@0 564
rlm@0 565 #+begin_src clojure :results output :exports both
rlm@0 566 (clojure.pprint/pprint
rlm@0 567 (pokemon.types/susceptibility [:grass :ice]))
rlm@0 568 #+end_src
rlm@0 569
rlm@0 570 #+results:
rlm@0 571 #+begin_example
rlm@0 572 {:water 1/2,
rlm@0 573 :psychic 1,
rlm@0 574 :dragon 1,
rlm@0 575 :fire 4,
rlm@0 576 :ice 1,
rlm@0 577 :grass 1/2,
rlm@0 578 :ghost 1,
rlm@0 579 :poison 2,
rlm@0 580 :flying 2,
rlm@0 581 :normal 1,
rlm@0 582 :rock 2,
rlm@0 583 :electric 1/2,
rlm@0 584 :ground 1/2,
rlm@0 585 :fighting 2,
rlm@0 586 :dark 1,
rlm@0 587 :steel 2,
rlm@0 588 :bug 2}
rlm@0 589 #+end_example
rlm@0 590
rlm@0 591 This miserable combination is weak to 6 types and double-weak to
rlm@0 592 Fire. No pok\eacute{}mon in the games actually has this type.
rlm@0 593
rlm@0 594 * Conclusion
rlm@0 595
rlm@0 596 Searching for a type that is weak to everything takes a very long time
rlm@0 597 and fails to reveal any results. That's the problem with a search
rlm@0 598 over this large problem space --- if there's an easy solution, the
rlm@0 599 search will find it quickly, but it can be very hard to determine
rlm@0 600 whether there is actually a solution.
rlm@0 601
rlm@0 602 In the [[./lpsolve.org][next installment]], I'll use =lp_solve= to solve this problem in
rlm@0 603 a different way.
rlm@0 604
rlm@0 605
rlm@0 606 * COMMENT main program
rlm@0 607 #+begin_src clojure :noweb yes :tangle ../src/pokemon/types.clj :exports none
rlm@0 608 <<header>>
rlm@0 609 #+end_src
rlm@0 610
rlm@0 611 ## this is necessary to define pokemon-table inside the source code.
rlm@0 612
rlm@0 613 #+begin_src clojure :noweb yes :tangle ../src/pokemon/types.clj :var pokemon-table-gen-one=pokemon-table-gen-one :var pokemon-table-gen-two=pokemon-table-gen-two :exports none
rlm@0 614 <<data>>
rlm@0 615 #+end_src
rlm@0 616
rlm@0 617 #+begin_src clojure :noweb yes :tangle ../src/pokemon/types.clj :exports none
rlm@0 618 <<types>>
rlm@0 619 <<search>>
rlm@0 620 <<pokemon-search>>
rlm@0 621 <<old-school>>
rlm@0 622 <<weaknesses>>
rlm@0 623 <<weak-types>>
rlm@0 624 #+end_src
rlm@0 625
rlm@0 626
rlm@0 627
rlm@0 628
rlm@0 629
rlm@0 630
rlm@0 631
rlm@0 632
rlm@0 633
rlm@0 634
rlm@0 635
rlm@0 636
rlm@0 637
rlm@0 638
rlm@0 639
rlm@0 640
rlm@0 641
rlm@0 642