How rotate a vector in blueprint ?

[anonymous_user_4a89ca7d]

This is my function which draw ray:
https://image.noelshack.com/minis/2019/31/2/1564455243-b.png

This is my simple algorithm:
https://image.noelshack.com/minis/2019/31/2/1564455245-c.png

Index X and Y are float that i increment, for example:

It start at 5 and at each loop i change the value, 5 to 10, 10 to 15 …