# DTW
# Usage
This function is used to calculate the DTW distance between two input series.
Name: DTW
Input Series: Only support two input series. The types are both INT32 / INT64 / FLOAT / DOUBLE.
Output Series: Output a single series. The type is DOUBLE. There is only one data point in the series, whose timestamp is 0 and value is the DTW distance.
Note:
- If a row contains missing points, null points or
NaN
, it will be ignored; - If all rows are ignored,
0
will be output.
# Examples
Input series:
+-----------------------------+---------------+---------------+
| Time|root.test.d2.s1|root.test.d2.s2|
+-----------------------------+---------------+---------------+
|1970-01-01T08:00:00.001+08:00| 1.0| 2.0|
|1970-01-01T08:00:00.002+08:00| 1.0| 2.0|
|1970-01-01T08:00:00.003+08:00| 1.0| 2.0|
|1970-01-01T08:00:00.004+08:00| 1.0| 2.0|
|1970-01-01T08:00:00.005+08:00| 1.0| 2.0|
|1970-01-01T08:00:00.006+08:00| 1.0| 2.0|
|1970-01-01T08:00:00.007+08:00| 1.0| 2.0|
|1970-01-01T08:00:00.008+08:00| 1.0| 2.0|
|1970-01-01T08:00:00.009+08:00| 1.0| 2.0|
|1970-01-01T08:00:00.010+08:00| 1.0| 2.0|
|1970-01-01T08:00:00.011+08:00| 1.0| 2.0|
|1970-01-01T08:00:00.012+08:00| 1.0| 2.0|
|1970-01-01T08:00:00.013+08:00| 1.0| 2.0|
|1970-01-01T08:00:00.014+08:00| 1.0| 2.0|
|1970-01-01T08:00:00.015+08:00| 1.0| 2.0|
|1970-01-01T08:00:00.016+08:00| 1.0| 2.0|
|1970-01-01T08:00:00.017+08:00| 1.0| 2.0|
|1970-01-01T08:00:00.018+08:00| 1.0| 2.0|
|1970-01-01T08:00:00.019+08:00| 1.0| 2.0|
|1970-01-01T08:00:00.020+08:00| 1.0| 2.0|
+-----------------------------+---------------+---------------+
SQL for query:
select dtw(s1,s2) from root.test.d2
Output series:
+-----------------------------+-------------------------------------+
| Time|dtw(root.test.d2.s1, root.test.d2.s2)|
+-----------------------------+-------------------------------------+
|1970-01-01T08:00:00.000+08:00| 20.0|
+-----------------------------+-------------------------------------+