Java Reference
In-Depth Information
/** Convert the angle in degrees to an angle in radians */
public static double
toRadians(
double
degree)
/** Convert the angle in radians to an angle in degrees */
public static double
toDegrees(
double
radians)
/** Return the angle in radians for the inverse of sin */
public static double
asin(
double
a)
/** Return the angle in radians for the inverse of cos */
public static double
acos(
double
a)
/** Return the angle in radians for the inverse of tan */
public static double
atan(
double
a)
The parameter for
sin
,
cos
, and
tan
is an angle in radians. The return value for
asin
,
acos
, and
atan
is a degree in radians in the range between
-
p
/2
and
p
/2.
One degree is equal to
p
/180
in radians, 90 degrees is equal to
p
/2
in radians, and 30 degrees is equal to
p
/6
in radians.
For example,
Math.toDegrees(Math.PI /
2
)
returns
90.0
Math.toRadians(
30
)
returns
0.5236
(
same as
π
/6)
Math.sin(
0
)
returns
0.0
Math.sin(Math.toRadians(
270
))
returns
-1.0
Math.sin(Math.PI /
6
)
returns
0.5
Math.sin(Math.PI /
2
)
returns
1.0
Math.cos(
0
)
returns
1.0
Math.cos(Math.PI /
6
)
returns
0.866
Math.cos(Math.PI /
2
)
returns
0
Math.asin(
0.5
)
returns
0.523598333
(same as
π
/6
)
5.10.2 Exponent Methods
There are five methods related to exponents in the
Math
class:
/** Return e raised to the power of x (e
x
) */
public static double
exp(
double
x)
/** Return the natural logarithm of x (ln(x) = log
e
(x)) */
public static double
log(
double
x)
/** Return the base 10 logarithm of x (log
10
(x)) */
public static double
log10(
double
x)
/** Return a raised to the power of b (a
b
) */
public static double
pow(
double
a,
double
b)
/** Return the square root of x
for x >= 0 */
2
x
public static double
sqrt(
double
x)
For example,
Math.exp(
1
)
returns
2.71828
Math.log(Math.E)
returns
1.0
Math.log10(
10
)
returns
1.0
Math.pow(
2
,
3
)
returns
8.0
Math.pow(
3
,
2
)
returns
9.0
Math.pow(
3.5
,
2.5
)
returns
22.91765
