topic Re: How to extract the position of a char in a string? in Discussions

How to extract the position of a char in a string?

JMP2021 — Sat, 10 Jun 2023 23:42:25 GMT

I have the following column, which contains string of char, such as dot or char (no number and special char).

I want to generate a column that list out the position of the char which is not a dot. See an example below.

Is there any formula or script I can use in JMP??

·cgaagt··a··········· 2,3,4,5,6,7,10
··t·a·············c·· 3,5,19
·····················

Re: How to extract the position of a char in a string?

jthi — Wed, 12 Jan 2022 05:36:47 GMT

I think you will have to script it.

Convert the string to a list with Words(str, "")
Replace all values you aren't interested in with empty string (missing value) by using Substitute
Use Loc NonMissing to find indices of non missing values

Names Default To Here(1);

a = "·cgaagt··a···········";
b = "··t·a·············c··";
c = "·····················";
list_of_chars = Words(a, "");
Substitute Into(list_of_chars, "·", "");
Show(AsList(Loc Nonmissing(list_of_chars)));

a = "··t·a·············c··";
list_of_chars = Words(a, "");
Substitute Into(list_of_chars, "·", "");
Show(AsList(Loc Nonmissing(list_of_chars)));

a = "·····················";
list_of_chars = Words(a, "");
Substitute Into(list_of_chars, "·", "");
Show(AsList(Loc Nonmissing(list_of_chars)));

//As List(Loc Nonmissing(list_of_chars)) = {2, 3, 4, 5, 6, 7, 10};
//As List(Loc Nonmissing(list_of_chars)) = {3, 5, 19};
//As List(Loc Nonmissing(list_of_chars)) = {};

Re: How to extract the position of a char in a string?

txnelson — Wed, 12 Jan 2022 07:15:09 GMT

Expanding on @jthi great solution, I believe the best way to handle your issue is to create a new column to place the results in. Also, you indicated that not just a "." might be used as a special character. So the JSL below is a formula that can handle multiple special characters, and also returns the results in a new column. Just create a character column and cut and past the formula into it.

list_of_chars = Words( :strings, "" );
Substitute Into( list_of_chars, ".", "", "+", "", "/", "" );
charList = As List( Loc Nonmissing( list_of_chars ) );
Substr( Char( charList ), 2, Length( Char( charList ) ) - 2 );