nl_tokens: N : 个体基因数 K : 种群规模（种群稳定时的数量） genes : 基因 weights : 基因权重，影响出现的可能性大小 mutationRate : 基因突变率，大约有多少比例的基因需要突变 birthRate : 出生率 timeout : 最大时限
pl_tokens: function Population ( opts ) { // allow use object for gene var genes = opts . genes . map ( function ( gene , index ) { return <mask> ; } ) ; this . oriGenes = opts . genes ; this . fitness = function ( individual ) { individual = individual . map ( function ( geneIndex ) { return opts . genes [ geneIndex ] ; } ) ; return opts . fitness ( individual ) ; } ; this . genePool = GenePool ( genes , opts . N , opts . weights ) ; this . K = opts . K ; this . N = opts . N ; // the very first generation this . population = [ ] ; this . history = { } ; // 记住产生过的个体 // 默认尝试1000次仍无新结果则取消尝试 this . maxLoop = opts . maxLoop || 1000 ; this . birthRate = opts . birthRate ; this . mutationRate = opts . mutationRate ; }