Sort array alphabetically - educational🔶 OVERVIEW
• This educational script will sort an array of tickers alphabetically and place these values in an table , together with the according current price value next to each ticker .
🔶 SORT ALPHABETICALLY
🔹 I. We make a User Defined Type (UDT) obj , with:
· ticker - the string name of the ticker
· price - the current price (close)
• From this UDT we make an object obj.new() for each ticker
🔹 II. 2 array's are made:
• array of objects aObj , containing obj type obj.new() for every ticker
• array of strings sort , the ticker part of each object obj.new()
🔹 III. Now we make an object of each ticker with the createObject(sym ) function
object_1 = createObject("TICKER")
• the object object_1 consists off:
· ticker -> "TICKER"
· price -> current Daily close through request.security("TICKER") (non-repainting)
• object_1 will be added to the aObj array
• "TICKER" ( string ticker part of object ) will be added to the sort array
🔹 IV. The latter array is sorted alphabetically by using array.sort_indices()
EXAMPLE
originalArray = array.from("B", "A", "C")
indicesArray = // sorted indices
array.get(originalArray, 1) -> "A"
array.get(originalArray, 0) -> "B"
array.get(originalArray, 2) -> "C"
IMPORTANT
Alphabetically sorting is case sensitive , just like Java compareTo(String anotherString) !
• The comparison is based on the Unicode value of each character in the string, the lowest "Dec" values are sorted first in line.
• Comparing the "Dec" values at unicodelookup explains why default CAPITAL lettres will be sorted first,
• Default you would get this (A= 65, B= 66, a= 97, b= 98)
Aa
Ba
ab
bb
• Adding str.lower(string) in the toLowerCase() function will result to the following:
Aa
ab
Ba
bb
• (A= 65 is transformed to a= 97, ...)
• As a side note, should you write "AMZN" as "ÀMZN" this would be placed at the end, even after transforming to lower case the "Dec" values are higher (À= 192, à= 224).
• You can toggle "To Lower Case" to verify.
🔹 V. Values are placed in a table , using these sorted indices.
• With the usage of UDTs and objects , the current price has the same index in the aObj as their ticker ,
giving the advantage it is fairly easy to place every value correctly next to each other.
• The same can be done by make 2 separate arrays , 1 for the current price , the other for "TICKER" .
🔶 OTHER TECHNIQUES USED
• Alternative technique for adding comment
Instead of
// this is a comment
You can also do this:
_=" this is a comment "
• Alternate colour
· During a loop , alternate colour when i is even or odd , using the modulo operation (%) .
· This is the remainder when dividing.
EXAMPLE
· 3 % 2 = 1 -> 3 / 2 -> 1 * 2, 1 left (remainder)
· 4 % 2 = 0 -> 4 / 2 -> 2 * 2, 0 left (remainder)
· 5 % 2 = 1 -> 5 / 2 -> 2 * 2, 1 left (remainder)
for i = 0 to 10
even = i % 2 == 0
col = even ? thisColor : otherColor
• Adjust colour in script by using colour picker
Cheers!
