从函数返回对象（R）

Question

I don't understand why this snippet does not work. My understanding of the function return() is that it enables you to use an object that was created inside a function outside the function.

I have this simple function and I want to use product outside of my function. How can I do this? Or, alternatively, have I entirely missed the point of the return() function?

simple_fcn<- function(input1, input2)
{
        product = input1*input2
        return(product)
}

simple_fcn(2,5)

print(product)

Answer 1

You need to save the return argument when calling the function into a variable that is available in the global environment, ie try the following:

product_global <- simple_fcn(2, 5)
print(product_global)

Answer 2

In addition to Felipe's comment, to assign product to a variable in a function's parent environment you can do product <<- product or assign('product', product, 1) inside the function. For more flexible assignments see ?assign .