How to generate a local list with numbers in a simple way

[Shuoge Qian]

Hi all, I have a simple question. Say I want to process filenames or variable names with consecutive numbers such like "abc1xyz", "abc2xyz", "abc3xyz", "abc4xyz", ... , "abc100xyz", so I need to generate a local list of these names. Directly using local list "abc1xyz......" makes the code be too long if there are too many consecutive numbers, so I would like to ask if there is any simple way to generate local list with consecutive numbers like this? Many thanks in advance!

PS: I know that if I want to do loop. I can use forvalues x=1/100 and if I want to keep or drop variables I can use keep abc*xyz. But still, sometimes I need the list, for example when I need to keep variables with odd numbers in this list "abc1xyz", "abc2xyz", "abc3xyz", "abc4xyz", ... , "abc100xyz".

[Nick Cox]

forval j = 1/100 { 
     local wanted  abc`j'xyz
     // work with that  
}

[Shuoge Qian]

forval j = 1/100 {
local wanted abc`j'xyz
// work with that
}

Thank you for your quick reply!

I'm still a bit confusing. I try an example.
First i generate abc1xyz to abc100xyz

Code:
forvalues j=1/100{
gen abc`j'xyz=1
}

Then i generate list:

Code:
forvalues j=1/100{
local wanted abc`j'xyz
}

But the list only contain abc100xyz, for example, when I try to drop all variables:

Code:
drop `wanted'

Only the last one which is abc100xyz is dropped.

I actually want to generate a list like this: local list "abc1xyz abc2xyz abc3xyz abc4xyz abc5xyz abc6xyz... ..abc98xyz abc99xyz. abc100xyz"

Thank you in advance

[Shuoge Qian]

forval j = 1/100 {
local wanted abc`j'xyz
// work with that
}

And also, now I even do not know how to generate simple list like this: local list "1 2 3 4 5 6 7 8 9 10 11 12... ... 90 91 92 93 94 95 96 97 98 99 100", but directly typing this numbers makes the code be so long....

[Joro Kolev]

Try this:

. forvalues i = 1/100 {
  2. local l "`l' `i'"
  3. }

. dis "`l'"
 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 
> 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73
>  74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 1 2 3 4 5 6 7 8 9 10 
> 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45
>  46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 8
> 0 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
>  18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 5
> 2 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 
> 87 88 89 90 91 92 93 94 95 96 97 98 99 100

And also, now I even do not know how to generate simple list like this: local list "1 2 3 4 5 6 7 8 9 10 11 12... ... 90 91 92 93 94 95 96 97 98 99 100", but directly typing this numbers makes the code be so long....

[Nick Cox]

You already know how to call up the varlist through a wildcard, as you explained in #1.

In practice you rarely need the list otherwise, but it is naturally possible:

forval j = 1/100 { 
     local list `list' abc`j'xyz 
}

[Shuoge Qian]

Try this:

. forvalues i = 1/100 {
2. local l "`l' `i'"
3. }

. dis "`l'"
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38
> 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73
> 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 1 2 3 4 5 6 7 8 9 10
> 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45
> 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 8
> 0 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
> 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 5
> 2 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86
> 87 88 89 90 91 92 93 94 95 96 97 98 99 100

Thank you so much! I understand!

[Shuoge Qian]

You already know how to call up the varlist through a wildcard, as you explained in #1.

In practice you rarely need the list otherwise, but it is naturally possible:

forval j = 1/100 {
local list `list' abc`j'xyz
}

Got it! Thx