The decimal point is optional when representing a floating point number. The superior precision of double can be useful for accurately representing large numbers, since float can represent only seven or eight significant digits accurately. This superior accuracy, however, consumes twice the memory space of float. If it appears multiple times, several copies are made. A dataString can be used to store a memory address.
Addresses are unlikely to be compared, and each record can have a different address.
Unlike a dataString , only a single copy of a given string is stored in memory, no matter how many times it appears in the data. This saves memory for strings appearing many times. Comparing strings is also much quicker than comparing dataString s. Reading in strings can be slower than reading in dataStrings because it is necessary to look for duplications. An example of string use is a division name that appears once for each department in the division. If you are unsure whether to use a string or a dataString , use a string .