How Can You Convert a uint64 to an int64 Without Losing Information?

Converting uint64 to int64 without Information Loss

The provided code indeed converts the given uint64 value to an int64, but the resulting value (-1) is not the expected statistical representation. This is because, despite maintaining the bit values, the int64 data type interprets them with a different sign convention.

To avoid this discrepancy, you can use an encoder-decoder approach to preserve the original bit pattern. However, it's important to note that the conversion from uint64 to int64 using:

int64 y = int64(x)

does not alter the bit sequence. It simply applies the sign interpretation. Thus, the following conversion:

var x uint64 = 18446744073709551615
var y int64 = int64(x)

will result in:

x = 0xFFFFFFFFFFFFFFFF
y = 0xFFFFFFFFFFFFFFFF (as a signed int64)

In contrast, the encoder-decoder approach ensures that the bit representation is maintained intact, regardless of the sign convention.

For example, if you modify the uint64 value slightly:

var x uint64 = 18446744073709551615 - 3

The resulting int64 conversion:

var y int64 = int64(x)

will produce:

y = -4

This demonstrates that the bit representation is preserved and interpreted accurately as a signed integer.

The above is the detailed content of How Can You Convert a uint64 to an int64 Without Losing Information?. For more information, please follow other related articles on the PHP Chinese website!