melt(data,id.vars=c(),measure.vars=(),variable.name="",value.name="")
melt(muying3,id.vars = "采購員", measure.vars =c("北京在庫庫存","上海在庫庫存","廣州在庫庫存","成都在庫庫存","武漢在庫庫存","沈陽在庫庫存","其它機構庫存"),variable.name = "倉庫",value.name="合計總庫存" )
# "muying3$采購員" 是錯誤格式
dcast(data, formula, fun.aggregate = NULL, ..., margins = NULL,subset = NULL, fill = NULL, drop = TRUE value.var = guess_value(data)
dcast(data2,采購員~倉庫,value.var = "合計總庫存",fun.aggregate = sum)
#采購員~倉庫 不加引號 value.var 要指定內容
