I am having trouble finding how to do this properly.

I know there is a command atoi, but it changes a string to a number.

Im looking for a function(if there exists) to change/cast a number so it can be read as a string

ex.

5 = "5"
5.5 = "5.5

also, if there's any c++ reference website you can point me to for stuff such as this, it would be appreciated.(The C one is good, but need with string functions)