Difference between double and single quotation marks in fortran?

Question

I'm just starting out on Fortran and am confused with the usage of double vs single quotation marks.

Answer 1

They are equivalent. There is no difference in their usage.

You can employ this to print one of the quotation characters:

print *, "'"

print *, '"'

prints first ' and then ".

Note: You can also use two quote characters in a row to print one:

print *, """"

print *, ''''

prints first " and then '.

Answer 2

Functionally they have no difference. Just try to be consistent about which one you use. If your strings tend to have double quotes in them, use single quotes everywhere; if you use single quotes more often, use double quotes to delimit your strings.

As an additional note, it is possible to escape the quote character inside a string: (i.e. 'You\'re') but most people would suggest using it doubled up as they would find it more readable (i.e. 'You''re').