A real type defines a set of numbers that can be represented with floating-point notation. The table below gives the ranges and storage formats for the fundamental real types.Type Range Significant digits Size in bytes
Real48 2.9 x 10^–39 .. 1.7 x 10^38 11–12 6
Single 1.5 x 10^–45 .. 3.4 x 10^38 7–8 4
Double 5.0 x 10^–324 .. 1.7 x 10^308 15–16 8
Extended 3.6 x 10^–4951 .. 1.1 x 10^4932 19–20 10
Comp –2^63+1 .. 2^63 –1 19–20 8
Currency –922337203685477.5808.. 922337203685477.5807 19–20 8
The generic type Real, in its current implementation, is equivalent to Double.Type Range Significant digits Size in bytes
Real 5.0 x 10^–324 .. 1.7 x 10^308 15–16 8
一般情况用Extended
Real48 2.9 x 10^–39 .. 1.7 x 10^38 11–12 6
Single 1.5 x 10^–45 .. 3.4 x 10^38 7–8 4
Double 5.0 x 10^–324 .. 1.7 x 10^308 15–16 8
Extended 3.6 x 10^–4951 .. 1.1 x 10^4932 19–20 10
Comp –2^63+1 .. 2^63 –1 19–20 8
Currency –922337203685477.5808.. 922337203685477.5807 19–20 8
The generic type Real, in its current implementation, is equivalent to Double.Type Range Significant digits Size in bytes
Real 5.0 x 10^–324 .. 1.7 x 10^308 15–16 8
一般情况用Extended
6字节浮点数 real48
8字节浮点数 double
10字节浮点数 extnded