Question

How can I set a turtle’s color from an array?

Here’s my code but it doesn’t work:

let colors array:from-list ["red" "yellow" "blue" "pink"]
set index random 3
let c array:item colors index
set color array:item colors index

Which leads to this error:

can't set flower variable COLOR to non-number blue error while flower 101 running SET

Answer 1

In NetLogo color, the names of the 14 main colors, plus black and white are defined as constants, so no quotes are required. Also, since they are constants, they are treated like literal values, so you can use them in the bracketed list notation, otherwise, you’d need to use the (list . . . ) reporter to create that list.

Also, your use of an array may be more complicated than needed.

You can write:

let colors [ red green blue yellow ]
set index random 3
let c item colors index
set color c

As an extra bonus, you can use the one-of primitive to do all the above:

set color one-of [ red green blue yellow ]