使用mapply将两个参数应用于两个矩阵的每个行应用
我有一个函数f（x，y），该函数将两个向量参数作为输入，并将向量作为输出返回（所有相等长度n）。我正在尝试将此函数应用于两个MXN矩阵M1和M2的每一行以返回MXN矩阵，即M1和M2的每一行对应于输入参数x，y。
我使用以下语法：
M3 = mapply(f, M1, M2)
给出一个错误消息，指出F将NA作为输入参数。在我的测试示例中，
M1 = rbind(c(5,0,0,6),c(20,0,0,0))
M2 = rbind(c(5,15,25,55),c(0,0,5,40))
F（M1 [1，]，M2 [1，]），F（M1 [2，]，M2 [，2]）返回有效结果。我对Mapply的应用有什么问题？我以为这也许是第与列应用程序的问题，但是mapply（f，t（m1），t（m2））返回相同的错误，因此显然f正在喂食以外的其他行（或列（或列） M1，M2作为输入。
I have a function f(x,y) that takes two vector arguments as input and returns a vector as output (all of equal length n). I am trying to apply this function to every row of two m x n matrices M1 and M2 to return an m x n matrix, i.e. so that every row of M1 and of M2 correspond to input arguments x,y.
I used the following syntax:
M3 = mapply(f, M1, M2)
Which gives an error message stating that f is taking NA as input arguments. In my test example,
M1 = rbind(c(5,0,0,6),c(20,0,0,0))
M2 = rbind(c(5,15,25,55),c(0,0,5,40))
and f(M1[1,],M2[1,]), f(M1[2,],M2[,2]) return valid results. What is the problem with my application of mapply? I thought that perhaps it was an issue of row vs. column applications, but mapply(f, t(M1), t(M2)) returns the same error, so obviously f is being fed something other than the respective rows (or columns) of M1,M2 as input.
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如果我们想在每一行上申请，然后按行分开矩阵，然后以
list将其传递，请注意，
mapplymatrix （或vector）将在每个元素上循环IE，IE是单个元素，而在data.frame/data.table/tibble中，单个单元是列。通过按行分开（asplit-margin = 1），我们获得了向量的list，此处是单位是列表元素，为@ADAM在评论中提到的是，可能需要
t对（如果不使用f进行测试，则不清楚）If we want to apply on each row, then split the matrix by row and pass as a
listNote that
mapplyon amatrix(or avector) will loop over each element i.e. here the unit is a single element whereas indata.frame/data.table/tibble, the single unit is a column. By splitting by row (asplit-MARGIN = 1), we get alistof vectors and here the unit is a list elementAs @Adam mentioned in the comments, it may needs to be
transposed (Not clear without testing withf)