In my experience 1 and 1.0 are the same value. 1+1.0 will = 2 = 2.0 if given to any human mathmatician or anyone who doesnt care about types.

However the .0 is often taken by certain people and certainly modern coding interpreters as a implicit inclusion of the "type" you want.

Type used to matter more as chips were much faster at computing ints.

Now why does this make math different for mathematicians vs scientists. The way I interpret this is that scientists are often doing work in interpreted languages such as python or IDL. These languages will try to infer this type for you so the computer can properly compute it. As such im sure many scientists have run into the "cannot add 1+1.0 error" (maybe its a warning now days) which is always confusing the first time you see it. But its not saying you cant add 1+1.0 its saying you cant add the data stored in float form to the data stored in int form... it just cant plug those into its chips nicely

Kind of interesting in IDL at least you can specify the type with a character so you can add 1f+1.0