Math

Question 1

double/int/long/float abs(double a)

Answer 1

• Returns the absolute value of a double/int/long/float value.
• Also works with int/long/float arguments, returning int/long/float values respectively

Question 2

double/int/long/float max(arg, arg)

Answer 2

• Returns the bigger of two double/int/long/float values.
• Works with double/int/long/float arguments, returning double/int/long/float values respectively

Question 3

double/int/long/float min(arg, arg)

Answer 3

• Returns the smaller of two double/int/long/float values.
• Also works with int/long/float arguments, returning int/long/float values respectively

Question 4

double ceil(double a)

Answer 4

• Returns the smallest (closest to negative infinity) double value that is greater than or equal to the argument and is equal to a mathematical integer.

Question 5

double floor(double a)

Answer 5

• Returns the largest (closest to positive infinity) double value that is less than or equal to the argument and is equal to a mathematical integer.

Question 6

Math.rint() vs Math.round()

Answer 6

• double rint(double a): Returns the double value that is closest in value to the argument and is equal to a mathematical integer.
• long round(double a): Returns the closest long to the argument, with ties rounding to positive infinity.
• They differ in the way they handle rounding of integers which are on a boundary, like 4.5.
• For example for : double val = 4.5;
  
  • Math.rint(val) = 4.0
  • Math.round(val) = 5
  • As you can see Math.rint(4.5) actually rounds down, while Math.round(4.5) rounds up. That is the main difference