An unexpected space in names created by apply() paste0() on a expand.grid() in R

Here is my code:

data <- mtcars
colnames(data) <- apply(expand.grid(c('c'),1:11),1,paste0,collapse = "")
rownames(data) <- apply(expand.grid(c('r'),1:32),1,paste0,collapse = "")
data

Here is the output of data:

> data
     c 1 c 2   c 3 c 4  c 5   c 6   c 7 c 8 c 9 c10 c11
r 1 21.0   6 160.0 110 3.90 2.620 16.46   0   1   4   4
r 2 21.0   6 160.0 110 3.90 2.875 17.02   0   1   4   4
r 3 22.8   4 108.0  93 3.85 2.320 18.61   1   1   4   1
r 4 21.4   6 258.0 110 3.08 3.215 19.44   1   0   3   1
r 5 18.7   8 360.0 175 3.15 3.440 17.02   0   0   3   2
r 6 18.1   6 225.0 105 2.76 3.460 20.22   1   0   3   1
r 7 14.3   8 360.0 245 3.21 3.570 15.84   0   0   3   4
r 8 24.4   4 146.7  62 3.69 3.190 20.00   1   0   4   2
r 9 22.8   4 140.8  95 3.92 3.150 22.90   1   0   4   2
r10 19.2   6 167.6 123 3.92 3.440 18.30   1   0   4   4
r11 17.8   6 167.6 123 3.92 3.440 18.90   1   0   4   4
r12 16.4   8 275.8 180 3.07 4.070 17.40   0   0   3   3
r13 17.3   8 275.8 180 3.07 3.730 17.60   0   0   3   3
r14 15.2   8 275.8 180 3.07 3.780 18.00   0   0   3   3
r15 10.4   8 472.0 205 2.93 5.250 17.98   0   0   3   4
r16 10.4   8 460.0 215 3.00 5.424 17.82   0   0   3   4
r17 14.7   8 440.0 230 3.23 5.345 17.42   0   0   3   4
r18 32.4   4  78.7  66 4.08 2.200 19.47   1   1   4   1
r19 30.4   4  75.7  52 4.93 1.615 18.52   1   1   4   2
r20 33.9   4  71.1  65 4.22 1.835 19.90   1   1   4   1
r21 21.5   4 120.1  97 3.70 2.465 20.01   1   0   3   1
r22 15.5   8 318.0 150 2.76 3.520 16.87   0   0   3   2
r23 15.2   8 304.0 150 3.15 3.435 17.30   0   0   3   2
r24 13.3   8 350.0 245 3.73 3.840 15.41   0   0   3   4
r25 19.2   8 400.0 175 3.08 3.845 17.05   0   0   3   2
r26 27.3   4  79.0  66 4.08 1.935 18.90   1   1   4   1
r27 26.0   4 120.3  91 4.43 2.140 16.70   0   1   5   2
r28 30.4   4  95.1 113 3.77 1.513 16.90   1   1   5   2
r29 15.8   8 351.0 264 4.22 3.170 14.50   0   1   5   4
r30 19.7   6 145.0 175 3.62 2.770 15.50   0   1   5   6
r31 15.0   8 301.0 335 3.54 3.570 14.60   0   1   5   8
r32 21.4   4 121.0 109 4.11 2.780 18.60   1   1   4   2

If we look at the new names of data, there is a space in-between each of the column names "c 1", "c 2", … , "c 9", and in each of the row names "r 1", "r 2", …, "r 9". Is there a way to remove those spaces?

>Solution :

We may simply use paste directly, instead of looping

paste0('c', 1:11)
[1] "c1"  "c2"  "c3"  "c4"  "c5"  "c6"  "c7"  "c8"  "c9"  "c10" "c11"
paste0("r", 1:32)
 [1] "r1"  "r2"  "r3"  "r4"  "r5"  "r6"  "r7"  "r8"  "r9"  "r10" "r11" "r12" "r13" "r14" "r15" "r16" "r17" "r18" "r19" "r20"
[21] "r21" "r22" "r23" "r24" "r25" "r26" "r27" "r28" "r29" "r30" "r31" "r32"