[R] Error message: $ operator is invalid for atomic vectors

[arun]

HI,

The code was working perfectly fine yesterday and today, until half an hour ago.  Couldn't find any problems in the code. Still, I am getting error message.

myMatrix <- data.matrix(read.table(text="
Name            Age
ANTONY        27
IMRAN          30
RAJ                  22
NAHAS          32
GEO                42
", header=TRUE))

MinMaxArray  <- data.frame(MIN = 25,MAX=35)
myMatrix[myMatrix$Age<=MinMaxArray$MAX & myMatrix$Age>=MinMaxArray$MIN,]
#Error in myMatrix$Age : $ operator is invalid for atomic vectors


#Then, I tried Rui's code;
 inx <- MinMaxArray[[ "MIN" ]] <= myMatrix[, "Age"] & myMatrix[, "Age"]<= MinMaxArray[[ "MAX" ]]
 myMatrix[ inx , ]
     Name Age
[1,]    1  27
[2,]    3  30
[3,]    4  32
#Previously, this was also working fine.

Not sure what is happening.

A.K.