Is double division equal to integer division if there is no remainder?

Question

In the JVM, does the separation between two double values ​​always give the exact same result as the whole division?

With the following prerequisites:

• Department without a trace
• No division by zero
• Both xand yreally contain integers.

eg. in the following code

double x = ...;
int resultInt = ...;
double y = x * resultInt;
double resultDouble = y / x; // double division

is it resultDoublealways equal resultIntor may there be some loss of accuracy?

Answer 1

, x y int, -2147483648.0 / -1.0. , int .

int, double. , -2147483648.0 / -1.0, int double. double double.

, x y int.

Answer 2

, int :

• , double/float,
• .

, , int, Java double 52- , 32- .

:

1- (Im)

2- Java

:

- int → float double

Answer 3

The statement is true, except Integer.MIN_VALUEwhere the result of dividing two integers can fall out of the integer range.

    int n = Integer.MIN_VALUE;
    int m = -1;
    System.out.println(n / m);                          // -2147483648
    System.out.println((int) ((double)n / (double)m));  // 2147483647