Labelling only with the first letter of string in QGIS

Question

I have a field called "Genus" where there are string values, for example, the word 'Pinus'.

I want my label to show only the first letter of this word so in my example 'P'.

I was trying to use Function Editor. I was contriving with field.row[0], but I'm not sure with the rest of the syntax.

Maybe there is another solution for it?

Answer 1

Use this in your label composer, it should do the trick :

left("Genus", 1)

Here's a list of functions you can use in your expressions

Answer 2

Another way is to use the substr() function:

substr("FieldName", 1, 1)

Replace "FieldName" with the name of your field.

Output:

Answer 3

Another solution employs the regexp_substr() function:

regexp_substr("data", '^[[:alpha:]]|[0-9]')

Answer 4

There is also a solution that uses the array_to_string() function.

string_to_array("test", '')[1]

Note: here I am referring to the fist character via [1] and not [0] (because it is a space even though initially there is no space in the string).