首页 > 解决方案 > 如何重新缩放数据框,使每行在 R 中的大小为 1?

问题描述

这是我的矩阵和代码的示例。我想重新调整我的数据框,使每一行的大小为 1。我是 r 的新手,在教程中,讲师说“将行的每个元素除以行的大小”。但是我不确定如何获得行的大小或重新调整数据帧。所以我尝试使用apply()但是在使用sqrt(sum(sc_mydata[r,]^2))测试我的重新缩放后我没有得到 1,我 x 的结果应该是 1

#dataframe
myData <- myData[1:12]

#transpose
x <- t(myData)

#rescale the data
sc_mydata = apply(x[-1,], 1, scale)

#test rescale 
for (r in 1:nrow(sc_mydata)) {
  #test rescale if this  is equal to 1 then the rescaling worked 
  x <- sqrt(sum(sc_mydata[r,]^2))

  }


     atr1     atr2     atr3     atr4     atr5     atr6     atr7     atr8     atr9    atr10    atr11    atr12
1 -0.35975 -0.42125 -0.33200 -0.08900 -0.16175 -0.44275 -0.38925  0.02975 -0.68525 -0.27500
2  0.01950 -0.27875 -0.18450 -0.30775 -0.34625  0.00200 -0.12425 -0.29475 -0.35375 -0.09575 -0.39150  0.00225
3  0.08350 -0.23125 -0.28025 -0.28975 -0.37325  0.01525 -0.11725 -0.29775 -0.32325 -0.09500 -0.55850 -0.11700
4  0.02225 -0.23675 -0.22425 -0.33925 -0.37075 -0.00375 -0.18450 -0.29250 -0.38450 -0.00400 -0.38975 -0.13850
5  0.05125 -0.35400 -0.31425 -0.35700 -0.26650 -0.07725 -0.11275 -0.34125 -0.30575  0.00550 -0.57025 -0.20600
6  0.01650 -0.28350 -0.10775 -0.29775 -0.16250 -0.03675 -0.1360

标签: rvectorscalerescale

解决方案


If by "the magnitude of the row" your instructor means "the sum of the row", this works:


sc_mydata <- apply(x, 1, function(x) x / sum(x, na.rm = TRUE))
sc_mydata <- t(sc_mydata)


For some reason, the row-wise apply() function transposes the data frame, so I had to transpose it back. I don't use apply much (prefer the tidyverse tools to base R) so idk why that happens.


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