如何使用reshape/plyr汇总数据？

Question

我的数据看起来像这样:

                   model                aspect cover contour
1                        flowering ~ 1      2    52    2400
2   flowering ~ 1 + temp + precip:temp      1    52    2390
3        flowering ~ 1 + temp + precip      1    52    2390
4        flowering ~ 1 + temp + precip      1    52    2390
5 flowering ~ 1 + precip + precip:temp      1    52    2400
6 flowering ~ 1 + precip + precip:temp      1    52    2400

此数据集中有40,000行,包含54个唯一模型.

如何获得汇总数据集,显示每个模型在纵横x轮廓x覆盖组合中出现的次数？

Answer 1

plyr为这种特殊情况提供了优化的功能:

comboCount <- count(myData, c("model","aspect","cover","contour"))