seq(1, 10) or seq(1:10)

[Redha]

Hello,
I would like to ask question about the difference between using seq(1, 10) and seq(1:10) in R code.
Is there any mistake to use seq(1:10) when we like to generate the vector 1 2 3 4 5 6 7 8 9 10
Thank you in advance.
Redha

[technocrat]

@Redha

seq(1:10)

is fine, as is

seq(1,10)

The function also takes arguments for various options. See help(seq)

seq(0, 1, length.out = 11)
#>  [1] 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
seq(stats::rnorm(20)) # effectively 'along'
#>  [1]  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17 18 19 20
seq(1, 9, by = 2)     # matches 'end'
#> [1] 1 3 5 7 9
seq(1, 9, by = pi)    # stays below 'end'
#> [1] 1.000000 4.141593 7.283185
seq(1, 6, by = 3)
#> [1] 1 4
seq(1.575, 5.125, by = 0.05)
#>  [1] 1.575 1.625 1.675 1.725 1.775 1.825 1.875 1.925 1.975 2.025 2.075 2.125
#> [13] 2.175 2.225 2.275 2.325 2.375 2.425 2.475 2.525 2.575 2.625 2.675 2.725
#> [25] 2.775 2.825 2.875 2.925 2.975 3.025 3.075 3.125 3.175 3.225 3.275 3.325
#> [37] 3.375 3.425 3.475 3.525 3.575 3.625 3.675 3.725 3.775 3.825 3.875 3.925
#> [49] 3.975 4.025 4.075 4.125 4.175 4.225 4.275 4.325 4.375 4.425 4.475 4.525
#> [61] 4.575 4.625 4.675 4.725 4.775 4.825 4.875 4.925 4.975 5.025 5.075 5.125
seq(17) # same as 1:17, or even better seq_len(17)
#>  [1]  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17

[Redha]

Thank you a lot for your answer.
Best regards,
Redha

[jlacko]

Just to build a bit on the previous answer: while it is correct that seq(1, 10) and seq(1:10) are equivalent in result I don't think that combining colon operator and seq() function is the best of practices.

The reason is that in the seq(1:10) the sequence is generated in the 1:10 call, and the seq around it just wraps itin another sequence of length one.

To illustrate the point consider this seq(1:10, by = 2) which clearly is not equivalent to seq(1, 10, by = 2).

While it is to a certain extent a matter of style & taste I suggest sticking to the colon operator when an integer sequence of step one is desired.

[technocrat]

@jlacko

integer sequence of step one is desired.

I agree that 1:10 should be limited to that case.

[Redha]

Thank you for your answer.
Best regards,
Redha