我想插值多个 NA
称为 tester 的矩阵中的值。
这是测试器的一部分,只有 1 列 NA 值,在整个 744x6 矩阵中,其他列也有多个:
ZONEID TIMESTAMP U10 V10 U100 V100
1 20121022 12:00 -1.324032e+00 -2.017107e+00 -3.278166e+00 -5.880225574
1 20121022 13:00 -1.295168e+00 NA -3.130429e+00 -6.414975148
1 20121022 14:00 -1.285004e+00 NA -3.068829e+00 -7.101699541
1 20121022 15:00 -9.605904e-01 NA -2.332645e+00 -7.478168285
1 20121022 16:00 -6.268261e-01 -3.057278e+00 -1.440209e+00 -8.026791079
我已经安装了
zoo
打包并使用代码library(zoo)
.我曾尝试使用 na.approx
函数,但它以线性方式返回:na.approx(tester)
# Error ----> need at least two non-NA values to interpolate
na.approx(tester, rule = 2)
# Error ----> need at least two non-NA values to interpolate
na.approx(tester, x = index(tester), na.rm = TRUE, maxgap = Inf)
后来我试过:
Lines <- "tester"
library(zoo)
z <- read.zoo(textConnection(Lines), index = 2)[,2]
na.approx(z)
我再次得到相同的倍数
NA
值错误。我也试过:z <- zoo(tester)
index(Cz) <- Cz[,1]
Cz_approx <- na.approx(Cz)
同样的错误。
我一定是在做一些非常愚蠢的事情,但我真的很感激你的帮助。
最佳答案
您可以申请 na.approx
仅在至少有两个非 NA
的列上值。这里我使用 colSums
在 bool 矩阵上查找相关列。
# create a small matrix
m <- matrix(data = c(NA, 1, 1, 1, 1,
NA, NA, 2, NA, NA,
NA, NA, NA, NA, 2,
NA, NA, NA, 2, 3),
ncol = 5, byrow = TRUE)
m
# [,1] [,2] [,3] [,4] [,5]
# [1,] NA 1 1 1 1
# [2,] NA NA 2 NA NA
# [3,] NA NA NA NA 2
# [4,] NA NA NA 2 3
library(zoo)
# na.approx on the entire matrix does not work
na.approx(m)
# Error in approx(x[!na], y[!na], xout, ...) :
# need at least two non-NA values to interpolate
# find columns with at least two non-NA values
idx <- colSums(!is.na(m)) > 1
idx
# [1] FALSE FALSE TRUE TRUE TRUE
# interpolate 'TRUE columns' only
m[ , idx] <- na.approx(m[ , idx])
m
# [,1] [,2] [,3] [,4] [,5]
# [1,] NA 1 1 1.000000 1.0
# [2,] NA NA 2 1.333333 1.5
# [3,] NA NA NA 1.666667 2.0
# [4,] NA NA NA 2.000000 3.0
关于r - 用 R 插入多个 NA 值,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/25625476/