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Spoiler: εμφάνιση/απόκρυψη

Ρώτησα και στο φροντιστήριο αλλά και πάλι δεν έχουν ξεκαθαρίσει οι έννοιες στο κεφάλι μου.

MpoMp wrote:Γιατί στην float πρέπει στο τέλος της τιμής της να βάζουμε το f?

Επίσης γιατί να βάλουμε f στο τέλος της τιμής μιας double? Και διάβασα κάπου στα tutorial της oracle πως μπορούμε να βάλουμε και ένα d στο τέλος της τιμής μιας float. Γιατί?

# float: The float data type is a single-precision 32-bit IEEE 754 floating point. Its range of values is beyond the scope of this discussion, but is specified in section 4.2.3 of the Java Language Specification. As with the recommendations for byte and short, use a float (instead of double) if you need to save memory in large arrays of floating point numbers. This data type should never be used for precise values, such as currency. For that, you will need to use the java.math.BigDecimal class instead. Numbers and Strings covers BigDecimal and other useful classes provided by the Java platform.

# double: The double data type is a double-precision 64-bit IEEE 754 floating point. Its range of values is beyond the scope of this discussion, but is specified in section 4.2.3 of the Java Language Specification. For decimal values, this data type is generally the default choice. As mentioned above, this data type should never be used for precise values, such as currency.

stoupeace wrote: To 3o δεν ξερω τι βγαζει η oracle απο το μυαλό της

# float: The float data type is a single-precision 32-bit IEEE 754 floating point. Its range of values is beyond the scope of this discussion, but is specified in section 4.2.3 of the Java Language Specification. As with the recommendations for byte and short, use a float (instead of double) if you need to save memory in large arrays of floating point numbers. This data type should never be used for precise values, such as currency. For that, you will need to use the java.math.BigDecimal class instead. Numbers and Strings covers BigDecimal and other useful classes provided by the Java platform.

# double: The double data type is a double-precision 64-bit IEEE 754 floating point. Its range of values is beyond the scope of this discussion, but is specified in section 4.2.3 of the Java Language Specification. For decimal values, this data type is generally the default choice. As mentioned above, this data type should never be used for precise values, such as currency.

http://download.oracle.com/javase/tutor ... types.html

The floating point types (float and double) can also be expressed using E or e (for scientific notation), F or f (32-bit float literal) and D or d (64-bit double literal; this is the default and by convention is omitted).

double d1 = 123.4;
double d2 = 1.234e2; // same value as d1, but in scientific notation
float f1 = 123.4f;