read.table or read.csv without row index?

Hello all,

Probably my concepts about the data.frame and matrix and array in R
are not clear, I need some clarification to help me understand them
better.
M <- read.table("test1.csv",sep=",",row.names=NULL,header=T)
gives me: M as

  M1 M2 M3 M4 M5 M6 M7 M8 M9 M10
1  9 11 14 15 18 20 20 20 20  20
2  3  4  8  9 11 12 14 15 15  15
3  4  5  8  8  9  9  9  9  9   9
4  4  5  7  8  8  8  8  8  8   9

1. How can I read the csv file to:

  M1 M2 M3 M4 M5 M6 M7 M8 M9 M10
[1,]  9 11 14 15 18 20 20 20 20  20
[2,]  3  4  8  9 11 12 14 15 15  15
[3,]  4  5  8  8  9  9  9  9  9   9
[4,]  4  5  7  8  8  8  8  8  8   9

2. or how can convert the above M to a format with [1,],[2,] etc
instead of 1,2,etc?

3. How can I read a text file so that I can get:
  [,1] [,2] [,3] [,4] [,5]
[1,]  9 11 14 15 18
[2,]  3  4  8  9 11
[3,]  4  5  8  8  9
[4,]  4  5  7  8  8

(instead of having the columns names V1 to V5?)

Thank you for your help!

Regards,

      John
An embedded and charset-unspecified text was scrubbed...
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Really, this depends on what you are trying to do. What's the underlying
problem you are solving? You can save a data frame to a file without
the names, if that's the real question, but I can't think of any reason to
not want names within R.

A matrix does not have to have row and column names, but a dataframe
is required to have them. If none are specified, sequential values will be
assigned.
matrix(1:9, 3, 3)
[,1] [,2] [,3]
[1,]    1    4    7
[2,]    2    5    8
[3,]    3    6    9
data.frame(matrix(1:9, 3, 3))
X1 X2 X3
1  1  4  7
2  2  5  8
3  3  6  9

Sarah
Hello all,

Probably my concepts about the data.frame and matrix and array in R
are not clear, I need some clarification to help me understand them
better.

M <- read.table("test1.csv",sep=",",row.names=NULL,header=T)
gives me: M as

?M1 M2 M3 M4 M5 M6 M7 M8 M9 M10
1 ?9 11 14 15 18 20 20 20 20 ?20
2 ?3 ?4 ?8 ?9 11 12 14 15 15 ?15
3 ?4 ?5 ?8 ?8 ?9 ?9 ?9 ?9 ?9 ? 9
4 ?4 ?5 ?7 ?8 ?8 ?8 ?8 ?8 ?8 ? 9

1. How can I read the csv file to:

?M1 M2 M3 M4 M5 M6 M7 M8 M9 M10
[1,] ?9 11 14 15 18 20 20 20 20 ?20
[2,] ?3 ?4 ?8 ?9 11 12 14 15 15 ?15
[3,] ?4 ?5 ?8 ?8 ?9 ?9 ?9 ?9 ?9 ? 9
[4,] ?4 ?5 ?7 ?8 ?8 ?8 ?8 ?8 ?8 ? 9

2. or how can convert the above M to a format with [1,],[2,] etc
instead of 1,2,etc?

3. How can I read a text file so that I can get:
?[,1] [,2] [,3] [,4] [,5]
[1,] ?9 11 14 15 18
[2,] ?3 ?4 ?8 ?9 11
[3,] ?4 ?5 ?8 ?8 ?9
[4,] ?4 ?5 ?7 ?8 ?8

(instead of having the columns names V1 to V5?)

Thank you for your help!

Regards,

? ? ?John

Sarah Goslee
http://www.functionaldiversity.org
You need to convert to a matrix and remove names:
x <- read.table(textConnection("M1 M2 M3 M4 M5 M6 M7 M8 M9 M10
+ 1  9 11 14 15 18 20 20 20 20  20
+ 2  3  4  8  9 11 12 14 15 15  15
+ 3  4  5  8  8  9  9  9  9  9   9
+ 4  4  5  7  8  8  8  8  8  8   9"), header=TRUE)
closeAllConnections()
y <- as.matrix(x)
x
M1 M2 M3 M4 M5 M6 M7 M8 M9 M10
1  9 11 14 15 18 20 20 20 20  20
2  3  4  8  9 11 12 14 15 15  15
3  4  5  8  8  9  9  9  9  9   9
4  4  5  7  8  8  8  8  8  8   9
y
M1 M2 M3 M4 M5 M6 M7 M8 M9 M10
1  9 11 14 15 18 20 20 20 20  20
2  3  4  8  9 11 12 14 15 15  15
3  4  5  8  8  9  9  9  9  9   9
4  4  5  7  8  8  8  8  8  8   9
dimnames(y) <- NULL
y
[,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10]
[1,]    9   11   14   15   18   20   20   20   20    20
[2,]    3    4    8    9   11   12   14   15   15    15
[3,]    4    5    8    8    9    9    9    9    9     9
[4,]    4    5    7    8    8    8    8    8    8     9

Hello all,

Probably my concepts about the data.frame and matrix and array in R
are not clear, I need some clarification to help me understand them
better.

M <- read.table("test1.csv",sep=",",row.names=NULL,header=T)
gives me: M as

?M1 M2 M3 M4 M5 M6 M7 M8 M9 M10
1 ?9 11 14 15 18 20 20 20 20 ?20
2 ?3 ?4 ?8 ?9 11 12 14 15 15 ?15
3 ?4 ?5 ?8 ?8 ?9 ?9 ?9 ?9 ?9 ? 9
4 ?4 ?5 ?7 ?8 ?8 ?8 ?8 ?8 ?8 ? 9

1. How can I read the csv file to:

?M1 M2 M3 M4 M5 M6 M7 M8 M9 M10
[1,] ?9 11 14 15 18 20 20 20 20 ?20
[2,] ?3 ?4 ?8 ?9 11 12 14 15 15 ?15
[3,] ?4 ?5 ?8 ?8 ?9 ?9 ?9 ?9 ?9 ? 9
[4,] ?4 ?5 ?7 ?8 ?8 ?8 ?8 ?8 ?8 ? 9

2. or how can convert the above M to a format with [1,],[2,] etc
instead of 1,2,etc?

3. How can I read a text file so that I can get:
?[,1] [,2] [,3] [,4] [,5]
[1,] ?9 11 14 15 18
[2,] ?3 ?4 ?8 ?9 11
[3,] ?4 ?5 ?8 ?8 ?9
[4,] ?4 ?5 ?7 ?8 ?8

(instead of having the columns names V1 to V5?)

Thank you for your help!

Regards,

? ? ?John

______________________________________________
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https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.

Jim Holtman
Cincinnati, OH
+1 513 646 9390

What is the problem that you are trying to solve?