matrix() can't handle NaN (PR#193)

data<-read.table("~/junk.dat",header=TRUE, na.strings="NaN")
data

x<-unique(data$x)
y<-unique(data$y)
matrix(data$z,length(y),length(x))

On Tue, 11 May 1999, Kurt Hornik wrote:

wsi  writes:

Full_Name: Bill Simpson
Version: 0.64.1
OS: linux
Submission from: (NULL) (193.62.250.209)

Here is the data file:
x y z
1 1 1
1 2 2
2 1 NaN
2 2 4

data<-read.table("~/junk.dat",header=TRUE)

data

  x y   z
1 1 1   1
2 1 2   2
3 2 1 NaN
4 2 2   4

I forgot these steps:
x<-unique(data$x)
y<-unique(data$y)

matrix(data$z,length(y),length(x)) 

     [,1] [,2]
[1,]    1    4
[2,]    2    3

This is not the correct matrix.  It seems that NaNs screw up matrix().

Actually, data$z is a factor with one level NaN.

Geez, I why is data$z a factor?  That seems bizarre. It is supposed to be
the measured value (IV) at each combination of x and y. So what is the
right way to convert my original file?

I go through all this just to produce an image or contour or persp plot.

R> data$z
[1] 1   2   NaN 4  
Levels:  1 2 4 NaN

Weird! Is this because matrix() interprets NaN as a character string
instead of as an NaN (which is a "number", isn't it?)?

Why then isn't everything converted to a factor?

data$x

[1] 1 1 2 2

data$y

[1] 1 2 1 2

Also, why does matrix() work as I expect when the NaN in the file is
changed to a 0:

matrix(data$z,length(y),length(x))

     [,1] [,2]
[1,]    1    0
[2,]    2    4

It also works as I expect when the NaN is changed to an NA:

matrix(data$z,length(y),length(x))

     [,1] [,2]
[1,]    1   NA
[2,]    2    4

What you get is the codes of that, which I think is what you want.

NOPE! I want a matrix:
1	NaN
2	4

Bill

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