4

首先,这是tbl_df我正在使用的数据(简化):

> mytbldf
Source: local data frame [6 x 5]

  iso2c country year     var1      var2
1    BI Burundi 2011 4.486265  6.693711
2    BI Burundi 2012 3.939242  5.330326
3    BI Burundi 2013 4.286439  5.747370
4    UG  Uganda 2011 3.998849 10.025680
5    UG  Uganda 2012 4.606198 13.416311
6    UG  Uganda 2013 4.746322 15.981362

我想(以整洁的措辞)将 year 变量分布在var1和上var2。经过一些(...)迭代后,我发现了一种有效的语法:

> recast(mytbldf, iso2c + country ~ variable + year, measure.var = c("var1","var2"))
  iso2c country var1_2011 var1_2012 var1_2013 var2_2011 var2_2012 var2_2013
1    BI Burundi  4.486265  3.939242  4.286439  6.693711  5.330326   5.74737
2    UG  Uganda  3.998849  4.606198  4.746322 10.025680 13.416311  15.98136

三个问题:

1)如果我不指定measure.var =,我会收到以下错误:

> recast(mytbldf, iso2c + country ~ variable + year)
Using iso2c, country as id variables
Error in eval(expr, envir, enclos) : object 'year' not found

这是为什么?从recast's man,我认为它会measure.var作为所有其他变量?

2)那么,有没有办法避免指定measure.var?在我的真实案例中,有太多变量名称太长,无法显式指定它们。

3)有没有更好/更简单的方法来使用reshape2或者tidyr我错过了?

4

1 回答 1

5

您可以尝试可以采用多列的devel版本data.tablevalue.var

library(data.table)#v1.9.5+
dcast(setDT(mytbldf), iso2c+country~year, value.var=c('var1', 'var2'))
#    iso2c country 2011_var1 2012_var1 2013_var1 2011_var2 2012_var2 2013_var2
#1:    BI Burundi  4.486265  3.939242  4.286439  6.693711  5.330326   5.74737
#2:    UG  Uganda  3.998849  4.606198  4.746322 10.025680 13.416311  15.98136

或使用reshapefrombase R

reshape(mytbldf, idvar=c('iso2c', 'country'), timevar='year', 
                 direction='wide')
#  iso2c country var1.2011 var2.2011 var1.2012 var2.2012 var1.2013 var2.2013
#1    BI Burundi  4.486265  6.693711  3.939242  5.330326  4.286439   5.74737
#4    UG  Uganda  3.998849 10.025680  4.606198 13.416311  4.746322  15.98136

关于recast它只是melt+ dcast。因此,如果您没有指定id.varor measure.varin meltlong格式将与您预期的不同。对于recast,您可以指定id.var

  library(reshape2)
  recast(mytbldf, id.var=c('iso2c', 'country', 'year'),
            iso2c+country~variable+year)
  #  iso2c country var1_2011 var1_2012 var1_2013 var2_2011 var2_2012 var2_2013
  #1    BI Burundi  4.486265  3.939242  4.286439  6.693711  5.330326   5.74737
  #2    UG  Uganda  3.998849  4.606198  4.746322 10.025680 13.416311  15.98136

此外,如果您知道列索引,这将比键入名称更容易,

 recast(mytbldf, measure.var=4:5,  iso2c+country~variable+year)
 #   iso2c country var1_2011 var1_2012 var1_2013 var2_2011 var2_2012 var2_2013
 #1    BI Burundi  4.486265  3.939242  4.286439  6.693711  5.330326   5.74737
 #2    UG  Uganda  3.998849  4.606198  4.746322 10.025680 13.416311  15.98136
于 2015-05-04T15:22:04.303 回答