maybe a simple question, but I cannot figure out a good method to solve it. With a df like this one:
也许是一个简单的问题，但我无法找到解决它的好方法。像这样的df：
ID Year Temp ph
1 P1 1996 11.3 6.80
2 P1 1996 9.7 6.90
3 P1 1997 9.8 7.10
...
2000 P2 1997 10.5 6.90
2001 P2 1997 9.9 7.00
2002 P2 1997 10.0 6.93
if I want to know where the max value is I type:
如果我想知道我输入的最大值在哪里：
which.max(df$Temp)
and R print the index of the row, for example 665.
并且R打印行的索引，例如665。
So, if I want to read and extract the column with all the related values, I have to type:
所以，如果我想读取并提取包含所有相关值的列，我必须输入：
df[665,]
Isn't there a simpler way to know which ID is related to the max value of a specific column of the df?
有没有更简单的方法来知道哪个ID与df的特定列的最大值相关？
1 个解决方案
#1
33
You can include your which.max call as the first argument to your subsetting call:
您可以将which.max调用作为子集调用的第一个参数：
df[which.max(df$Temp),]
#1
33
You can include your which.max call as the first argument to your subsetting call:
您可以将which.max调用作为子集调用的第一个参数：
df[which.max(df$Temp),]