W3School
Lớp Toán trong Java có nhiều phương thức cho phép bạn thực hiện các nhiệm vụ toán học với các con số.
Math.max(x,y)
Math.max(x,y)
có thể tìm được số lớn nhất giữa x và y. Với ví dụ bên dưới kết quả trả về sẽ là 10.
Math.max(5, 10); // Output: 10
Math.min(x,y)
The Math.min(x,y)
có thể tìm được số nhỏ nhất giữa x và y. Với ví dụ bên dưới kết quả trả về sẽ là 5.
Math.min(5, 10);
Math.sqrt(x)
The Math.sqrt(x)
method returns the square root of x:
Math.sqrt(64);
Math.abs(x)
The Math.abs(x)
method returns the absolute (positive) value of x:
Math.abs(-4.7);
Random Numbers
Math.random()
returns a random number between 0.0 (inclusive), and 1.0 (exclusive):
Math.random();
To get more control over the random number, e.g. you only want a random number between 0 and 100, you can use the following formula:
int randomNum = (int)(Math.random() * 101); // 0 to 100
A list of all Math methods can be found in the table below:
Method | Description | Return Type |
---|---|---|
abs(x) | Returns the absolute value of x | double|float|int|long |
acos(x) | Returns the arccosine of x, in radians | double |
asin(x) | Returns the arcsine of x, in radians | double |
atan(x) | Returns the arctangent of x as a numeric value between -PI/2 and PI/2 radians | double |
atan2(y,x) | Returns the angle theta from the conversion of rectangular coordinates (x, y) to polar coordinates (r, theta). | double |
cbrt(x) | Returns the cube root of x | double |
ceil(x) | Returns the value of x rounded up to its nearest integer | double |
copySign(x, y) | Returns the first floating point x with the sign of the second floating point y | double |
cos(x) | Returns the cosine of x (x is in radians) | double |
cosh(x) | Returns the hyperbolic cosine of a double value | double |
exp(x) | Returns the value of Ex | double |
expm1(x) | Returns ex -1 | double |
floor(x) | Returns the value of x rounded down to its nearest integer | double |
getExponent(x) | Returns the unbiased exponent used in x | int |
hypot(x, y) | Returns sqrt(x2 +y2) without intermediate overflow or underflow | double |
IEEEremainder(x, y) | Computes the remainder operation on x and y as prescribed by the IEEE 754 standard | double |
log(x) | Returns the natural logarithm (base E) of x | double |
log10(x) | Returns the base 10 logarithm of x | double |
log1p(x) | Returns the natural logarithm (base E) of the sum of x and 1 | double |
max(x, y) | Returns the number with the highest value | double|float|int|long |
min(x, y) | Returns the number with the lowest value | double|float|int|long |
nextAfter(x, y) | Returns the floating point number adjacent to x in the direction of y | double|float |
nextUp(x) | Returns the floating point value adjacent to x in the direction of positive infinity | double|float |
pow(x, y) | Returns the value of x to the power of y | double |
random() | Returns a random number between 0 and 1 | double |
round(x) | Returns the value of x rounded to its nearest integer | int |
rint(x) | Returns the double value that is closest to x and equal to a mathematical integer | double |
signum(x) | Returns the sign of x | double |
sin(x) | Returns the sine of x (x is in radians) | double |
sinh(x) | Returns the hyperbolic sine of a double value | double |
sqrt(x) | Returns the square root of x | double |
tan(x) | Returns the tangent of an angle | double |
tanh(x) | Returns the hyperbolic tangent of a double value | double |
toDegrees(x) | Converts an angle measured in radians to an approx. equivalent angle measured in degrees | double |
toRadians(x) | Converts an angle measured in degrees to an approx. angle measured in radians | double |
ulp(x) | Returns the size of the unit of least precision (ulp) of x | double|float |
Note: All Math methods are static
.
W3School