Julia - Language - Functions - Optional Arguments

Functions in Julia can have optional input parameters. The optional input parameters are placed in the last. To make a parameter optional we provide a default value to it.

$ julia
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julia> function multiplyNos(a,b,c=1)
       prod = a*b*c
       println("we have the values of a = $a ; b= $b; c= $c")
       println("product of numbers = $prod \n")
       end
multiplyNos (generic function with 2 methods)


In this example, c is a optional argument. This is beacause it is having a default value of 1. That means, In case the third value is not provided - then it is considered as 1.


julia> multiplyNos(5,6)
we have the values of a = 5 ; b= 6; c= 1
product of numbers = 30 

Now when I pass the third value as parameter. It overrides the default value. 

julia> multiplyNos(5,6,2)
we have the values of a = 5 ; b= 6; c= 2
product of numbers = 60 

julia>