R - problems converting txt to read in R

Question

I have a '.xls' that I passed to '.txt' for the R reading, no problem. The point is that by opening '.txt' in R with read.table, it shows me as a single table, in a single R position.

> x
        V1
1     X
2    30.80
3     0.00
4     0.00
5     2.10
6     0.00
7     0.00
8     0.00
9    85.40
10    0.00
11    0.20
12    0.00
13    0.00
14    0.00
15    0.00
16    0.00
17    0.00
18    0.20
19    0.00
20   11.70
21    0.00
22   13.60
23    0.00
24   24.70
25   66.80
26    0.00
27    3.70
28   46.20
29  416.10
30   90.80
31    0.00
32    0.00
33    0.00
34   40.10
35   23.60
36   63.20
37   54.30
38   20.20
39   30.00
40   23.00
41    1.80
42    2.00
43   31.20
44   20.20
45  150.60
46   50.80
47    3.30
48    4.00
49   10.40
50    0.70
51    8.60
52    0.00
53    0.00
54    9.30
55    0.00
56    0.00
57  176.70
58    4.90
59   68.80
60   17.70
61    9.80
62    9.60
63    0.00
64   47.00
65    0.00
66    0.00
67    2.10
68    0.00
69  144.60
70   83.10
71   55.30
72    3.50
73    0.00
74    0.00
75    5.50
76   47.80
77   52.60
78  154.10
79   47.60
80   13.40
81    0.00
82   37.10
83    0.00
84    0.00
85    0.00
86   27.40
87    0.00
88    0.00
89   40.60
90   67.80
91    0.00
92    0.00
93   19.00
94  154.30
95   14.60
96    0.00
97    9.20
98    0.00
99    0.00
100   0.00
101   0.00
102   0.00
103 147.70
104 108.40
105  55.80
106  37.60
107  62.80
108  80.00
109  51.40
110  23.60
111  10.80
112  12.00
113   0.00

When I do a simple 'for' so that it puts each value in a position to read R, it changes my values. And it’s not rounding, because the figures aren’t even close.

xnovo<-seq(1,113)

for (i in 1:113){
xnovo[i]<-x[i,1][1]}
> xnovo
  [1] 67 29  1  1 23  1  1  1 60  1  2  1  1  1  1  1  1  2  1  7  1 10  1 26 54
 [26]  1 33 40 39 62  1  1  1 37 25 53 48 22 28 24 19 21 30 22 14 45 31 36  4  3
 [51] 61  1  1 64  1  1 17 44 56 18 66 65  1 41  1  1 23  1 11 58 50 32  1  1 49
 [76] 43 47 15 42  9  1 34  1  1  1 27  1  1 38 55  1  1 20 16 12  1 63  1  1  1
[101]  1  1 13  6 51 35 52 57 46 25  5  8  1

Someone knows how to fix this?

Answer 1

You can solve this problem by asking R skip the first line of the text file, using the argument skip = 1 inside the command read.table:

x <- read.table(file = "file.txt", skip = 1)
dim(x)
summary(x)
## [1] 112   1
summary(x)
## V1        
## Min.   :  0.00  
## 1st Qu.:  0.00  
## Median :  5.20  
## Mean   : 28.96  
## 3rd Qu.: 40.23  
## Max.   :416.10

Answer 2

The problem is in the first element of the column V1 be an alphabetical value ("X"). So R reads the whole column as being:

• class "factor" if you have stringsAsFactors = TRUE or have nothing, since this is the default value. This seems to be the case for the question. Factors are encoded internally by R as consecutive integers starting at 1. The first level should be "0.00" and corresponds to the whole 1, then comes the level "0.20" which corresponds to the 2, etc..
• class "character" if you have stringsAsFactors = FALSE.

In both cases you must remove this value "X" and then convert to numeric.

x <- read.table(file = "dados.txt", header = TRUE)

str(x)
#'data.frame':  113 obs. of  1 variable:
#$ V1: Factor w/ 66 levels "0.00","0.20",..: 66 32 1 1 22 1 1 1 60 1 ...


if(any(x[[1]] == "X")) x <- x[-which(x[[1]] == "X"), , drop = FALSE]
x[[1]] <- as.numeric(as.character(x[[1]]))

Then to create the vector xnovo does not need cycles for or others, just do

xnovo <- x[[1]]