Such as: float x；;
x = 1.2；
Where x is a floating-point type, but 1.2 is a double-precision type. Because it is a constant, the compiler is called const double. Double cannot be implicitly converted to float, but can be changed to x =1.2f; Or x =1.2f; Do it.
Extended data:
The difference between double precision and floating point
The main differences between the two are as follows:
1. The number of bytes in memory is different:
Single-precision floating-point numbers occupy 4 bytes in machine memory.
Double-precision floating-point numbers occupy 8 bytes in machine memory.
2. The significant digits are different:
Single-precision floating point number with 8 significant digits
Significant bits of 16 double-precision floating-point number
3. Value range:
The range of single-precision floating-point numbers is -3.40E+38~3.40E+38.
The expression range of double-precision floating-point numbers is-1.79e+308 ~-1.79e+308.
4. The processing speed in the program is different:
Generally speaking, the CPU can process single-precision floating-point numbers faster than double-precision floating-point numbers.