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算数运算符和函数

大约 3 分钟

算数运算符和函数

算数运算符

一元算数运算符

支持的运算符:+, -

输入数据类型要求:INT32, INT64, FLOAT, DOUBLE

输出数据类型:与输入数据类型一致

二元算数运算符

支持的运算符:+, -, *, /, %

输入数据类型要求:INT32, INT64, FLOATDOUBLE

输出数据类型:DOUBLE

注意:当某个时间戳下左操作数和右操作数都不为空(null)时,二元运算操作才会有输出结果

使用示例

例如:

select s1, - s1, s2, + s2, s1 + s2, s1 - s2, s1 * s2, s1 / s2, s1 % s2 from root.sg.d1

结果:

+-----------------------------+-------------+--------------+-------------+-------------+-----------------------------+-----------------------------+-----------------------------+-----------------------------+-----------------------------+
|                         Time|root.sg.d1.s1|-root.sg.d1.s1|root.sg.d1.s2|root.sg.d1.s2|root.sg.d1.s1 + root.sg.d1.s2|root.sg.d1.s1 - root.sg.d1.s2|root.sg.d1.s1 * root.sg.d1.s2|root.sg.d1.s1 / root.sg.d1.s2|root.sg.d1.s1 % root.sg.d1.s2|
+-----------------------------+-------------+--------------+-------------+-------------+-----------------------------+-----------------------------+-----------------------------+-----------------------------+-----------------------------+
|1970-01-01T08:00:00.001+08:00|          1.0|          -1.0|          1.0|          1.0|                          2.0|                          0.0|                          1.0|                          1.0|                          0.0|
|1970-01-01T08:00:00.002+08:00|          2.0|          -2.0|          2.0|          2.0|                          4.0|                          0.0|                          4.0|                          1.0|                          0.0|
|1970-01-01T08:00:00.003+08:00|          3.0|          -3.0|          3.0|          3.0|                          6.0|                          0.0|                          9.0|                          1.0|                          0.0|
|1970-01-01T08:00:00.004+08:00|          4.0|          -4.0|          4.0|          4.0|                          8.0|                          0.0|                         16.0|                          1.0|                          0.0|
|1970-01-01T08:00:00.005+08:00|          5.0|          -5.0|          5.0|          5.0|                         10.0|                          0.0|                         25.0|                          1.0|                          0.0|
+-----------------------------+-------------+--------------+-------------+-------------+-----------------------------+-----------------------------+-----------------------------+-----------------------------+-----------------------------+
Total line number = 5
It costs 0.014s

数学函数

目前 IoTDB 支持下列数学函数,这些数学函数的行为与这些函数在 Java Math 标准库中对应实现的行为一致。

函数名输入序列类型输出序列类型必要属性参数Java 标准库中的对应实现
SININT32 / INT64 / FLOAT / DOUBLEDOUBLEMath#sin(double)
COSINT32 / INT64 / FLOAT / DOUBLEDOUBLEMath#cos(double)
TANINT32 / INT64 / FLOAT / DOUBLEDOUBLEMath#tan(double)
ASININT32 / INT64 / FLOAT / DOUBLEDOUBLEMath#asin(double)
ACOSINT32 / INT64 / FLOAT / DOUBLEDOUBLEMath#acos(double)
ATANINT32 / INT64 / FLOAT / DOUBLEDOUBLEMath#atan(double)
SINHINT32 / INT64 / FLOAT / DOUBLEDOUBLEMath#sinh(double)
COSHINT32 / INT64 / FLOAT / DOUBLEDOUBLEMath#cosh(double)
TANHINT32 / INT64 / FLOAT / DOUBLEDOUBLEMath#tanh(double)
DEGREESINT32 / INT64 / FLOAT / DOUBLEDOUBLEMath#toDegrees(double)
RADIANSINT32 / INT64 / FLOAT / DOUBLEDOUBLEMath#toRadians(double)
ABSINT32 / INT64 / FLOAT / DOUBLE与输入序列的实际类型一致Math#abs(int) / Math#abs(long) /Math#abs(float) /Math#abs(double)
SIGNINT32 / INT64 / FLOAT / DOUBLEDOUBLEMath#signum(double)
CEILINT32 / INT64 / FLOAT / DOUBLEDOUBLEMath#ceil(double)
FLOORINT32 / INT64 / FLOAT / DOUBLEDOUBLEMath#floor(double)
ROUNDINT32 / INT64 / FLOAT / DOUBLEDOUBLEplaces:四舍五入有效位数,正数为小数点后面的有效位数,负数为整数位的有效位数Math#rint(Math#pow(10,places))/Math#pow(10,places)
EXPINT32 / INT64 / FLOAT / DOUBLEDOUBLEMath#exp(double)
LNINT32 / INT64 / FLOAT / DOUBLEDOUBLEMath#log(double)
LOG10INT32 / INT64 / FLOAT / DOUBLEDOUBLEMath#log10(double)
SQRTINT32 / INT64 / FLOAT / DOUBLEDOUBLEMath#sqrt(double)

例如:

select s1, sin(s1), cos(s1), tan(s1) from root.sg1.d1 limit 5 offset 1000;

结果:

+-----------------------------+-------------------+-------------------+--------------------+-------------------+
|                         Time|     root.sg1.d1.s1|sin(root.sg1.d1.s1)| cos(root.sg1.d1.s1)|tan(root.sg1.d1.s1)|
+-----------------------------+-------------------+-------------------+--------------------+-------------------+
|2020-12-10T17:11:49.037+08:00|7360723084922759782| 0.8133527237573284|  0.5817708713544664| 1.3980636773094157|
|2020-12-10T17:11:49.038+08:00|4377791063319964531|-0.8938962705202537|  0.4482738644511651| -1.994085181866842|
|2020-12-10T17:11:49.039+08:00|7972485567734642915| 0.9627757585308978|-0.27030138509681073|-3.5618602479083545|
|2020-12-10T17:11:49.040+08:00|2508858212791964081|-0.6073417341629443| -0.7944406950452296| 0.7644897069734913|
|2020-12-10T17:11:49.041+08:00|2817297431185141819|-0.8419358900502509| -0.5395775727782725| 1.5603611649667768|
+-----------------------------+-------------------+-------------------+--------------------+-------------------+
Total line number = 5
It costs 0.008s

ROUND

例如:

select s4,round(s4),round(s4,2),round(s4,-1) from root.sg1.d1 
+-----------------------------+-------------+--------------------+----------------------+-----------------------+
|                         Time|root.db.d1.s4|ROUND(root.db.d1.s4)|ROUND(root.db.d1.s4,2)|ROUND(root.db.d1.s4,-1)|
+-----------------------------+-------------+--------------------+----------------------+-----------------------+
|1970-01-01T08:00:00.001+08:00|    101.14345|               101.0|                101.14|                  100.0|
|1970-01-01T08:00:00.002+08:00|    20.144346|                20.0|                 20.14|                   20.0|
|1970-01-01T08:00:00.003+08:00|    20.614372|                21.0|                 20.61|                   20.0|
|1970-01-01T08:00:00.005+08:00|    20.814346|                21.0|                 20.81|                   20.0|
|1970-01-01T08:00:00.006+08:00|     60.71443|                61.0|                 60.71|                   60.0|
|2023-03-13T16:16:19.764+08:00|    10.143425|                10.0|                 10.14|                   10.0|
+-----------------------------+-------------+--------------------+----------------------+-----------------------+
Total line number = 6
It costs 0.059s

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