There are times when you should request copies of your records: 1  Permanent Change of Station. 2  Deploying. 3  Retiring.
0. EXPERT ANSWER. Double coincidence of wants refers to a situation in a barter system where the goods or services offered by a seller are exactly the same as that required by a buyer and vice versa.
In languages like C and FORTRAN (where a double is called double precision), a double is typically understood to have twice the number of bits as a float. This isn't always true, although a double will always have at least as many bits of precision as a float in any sane implementation.