Default values of the parameters

### 11.1.4 Default values of the parameters

You can give the parameters of a function default values by putting parameter=value in the parameter list of the function. For example, if you define a function

    f(x,y=5,z) := {
    return x*y*z;
    }

then

f(1,2,3)

will return the product 1*2*3=6. If you give f only two values as input,

f(3,4)

then these values will be given to the parameters which don’t have default values; in this case, y will get its default value 5 while 3 and 4 will be assigned to x and z, respectively. The result will be x*y*z=3*5*4=60.