本文介绍了R - 检查矢量对其他矢量的元素的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧! 问题描述 29岁程序员,3月因学历无情被辞! 考虑这些数据框: A = data.frame(par = c('long A story','long C story','blabla D'),val = 1:3) B = data.frame(par = c('Z','D','A'),val = letters [1:3]) B列'par'的每个元素应与A列par相匹配。 如果有匹配的话,应该在A中标注。 [这会给出一列用于合并A和B的公共值。] $ $ $ $ $ $ $ $ $ $ A $变换(A,label = c('A','NA', 'D')) 这怎么办? Henk 解决方案要做你想要的东西,试试 A = data.frame(par = c('long A story','long C story','blabla D'),val = 1:3) B = data.frame(par = c('Z','D','A'),val = letters [1:3]) A $ label for(x in B $ par){ is.match< - lapply(A $ par,function(y)grep(x,y)) A $ label [which(is.match> ; 0)] } (我假设你的意思是大写A在你的例子中 A = transform(a,label = c('A','NA','D'));在这种情况下,它们完全匹配)。编辑:我看到你做了编辑。他们确实匹配。 上述方法仅适用于只有一个B适合每个A的情况(换句话说,可以有多个对B而言不是多个B到A)。这是因为你在输出中需要的结构。 I would like to match the elements of a column in a dataframe against another dataframe.Consider these dataframes:A=data.frame(par=c('long A story','long C story', 'blabla D'),val=1:3)B=data.frame(par=c('Z','D','A'),val=letters[1:3])Each element of B column 'par' should be matched against A column par.If there is a match, it should be labeled in A.[This then gives a column of common values for merging A and B].The desired result is therefore: A=transform(A,label=c('A','NA','D'))How can this be done?Henk 解决方案 To do what you're asking for, tryA=data.frame(par=c('long A story','long C story', 'blabla D'),val=1:3)B=data.frame(par=c('Z','D','A'),val=letters[1:3])A$label <- NAfor (x in B$par){ is.match <- lapply(A$par,function(y) grep(x, y)) A$label[which(is.match > 0)] <- x}(I assumed you meant a capital A in your example A=transform(a,label=c('A','NA','D')); in that case, these match exactly). EDIT: I see you made that edit. They do match then.The above method will work only if there is exactly one B that fits every A (in other words, there can be multiple As to a B but not multiple Bs to an A). This is because of the structure you want in the output. 这篇关于R - 检查矢量对其他矢量的元素的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持! 上岸,阿里云!
06-05 08:50