From your script seems that you are from Brazil. You might want to take a look in this course I am giving now. The material has a series of indications on how to use Julia productively:
https://github.com/m3g/CKP/blob/master/disciplina/simulacoes2.pdf
But basically, writing very quick scripts is not what Julia is the best for.
This post may also help you in developing a good workflow: Julia REPL flow coming from Matlab - #5 by lmiq