# Custom function
eKuiper can customize functions. For the development, compilation and use of functions, please see here.
# echo plugin
| Function | Example | Description |
|---|---|---|
| echo | echo(avg) | Output parameter value as it is |
echo(avg) example
Assuming the type of avg is int and the value is 30, the result is:
[{"r1":30}]SELECT echo(avg) as r1 FROM test;1
# countPlusOne plugin
| Function | Example | Description |
|---|---|---|
| countPlusOne | countPlusOne(avg) | Output the value of the parameter length plus one |
countPlusOne(avg) example
Assuming the type of avg is []int and the value is
[1,2,3], the result is:[{"r1":4}]SELECT countPlusOne(avg) as r1 FROM test;1
# accumulateWordCount plugin
| Function | Example | Description |
|---|---|---|
| accumulateWordCount | accumulateWordCount(avg,sep) | The function counts how many words there are |
accumulateWordCount(avg,sep) example
Assuming that the avg type is string and the value is
My name is Bob, the sep type is string and the value is a space, the result is:[{"r1":4}]SELECT accumulateWordCount(avg,sep) as r1 FROM test;1
# Image processing plugin
Image processing currently only supports the formats of png and jpeg
| Function | Example | Description |
|---|---|---|
| resize | resize(avg,width, height) | Create a scaled image with new dimensions (width, height). If width or height is set to 0, it is set to the reserved value of aspect ratio |
| thumbnail | thumbnail(avg,maxWidth, maxHeight) | Reduce the image that retains the aspect ratio to the maximum size (maxWidth, maxHeight). |
resize(avg,width, height) example
The avg type is []byte.
SELECT resize(avg,width,height) as r1 FROM test;1
thumbnail(avg,maxWidth, maxHeight) example
The avg type is []byte.
SELECT countPlusOne(avg,maxWidth, maxHeight) as r1 FROM test;1
# Geohash plugin
| Function | Example | Description |
|---|---|---|
| geohashEncode | geohashEncode(la,lo float64)(string) | Encode latitude and longitude as a string |
| geohashEncodeInt | geohashEncodeInt(la,lo float64)(uint64) | Encode latitude and longitude as an unsigned integer |
| geohashDecode | geohashDecode(hash string)(la,lo float64) | Decode a string into latitude and longitude |
| geohashDecodeInt | geohashDecodeInt(hash uint64)(la,lo float64) | Decode an unsigned integers into latitude and longitude |
| geohashBoundingBox | geohashBoundingBox(hash string)(string) | Returns the area encoded by a string |
| geohashBoundingBoxInt | geohashBoundingBoxInt(hash uint64)(string) | Returns the area encoded by an unsigned integer |
| geohashNeighbor | geohashNeighbor(hash string,direction string)(string) | Returns the neighbor in the corresponding direction of a string (Direction list: North NorthEast East SouthEast South SouthWest West NorthWest) |
| geohashNeighborInt | geohashNeighborInt(hash uint64,direction string)(uint64) | Returns the neighbor in the corresponding direction of an unsigned integer (Direction list: North NorthEast East SouthEast South SouthWest West NorthWest) |
| geohashNeighbors | geohashNeighbors(hash string)([]string) | Return all neighbors of a string |
| geohashNeighborsInt | geohashNeighborsInt(hash uint64)([]uint64) | Return all neighbors of an unsigned integer |
geohashEncode example
- Input:
{"lo" :131.036192,"la":-25.345457} - Output:
{"geohashEncode":"qgmpvf18h86e"}
SELECT geohashEncode(la,lo) FROM test
geohashEncodeInt example
- Input:
{"lo" :131.036192,"la":-25.345457} - Output:
{"geohashEncodeInt":12963433097944239317}
SELECT geohashEncodeInt(la,lo) FROM test
geohashDecode example
- Input:
{"hash" :"qgmpvf18h86e"} - Output:
{"geohashDecode":{"Longitude":131.036192,"Latitude":-25.345457099999997}}
SELECT geohashDecode(hash) FROM test
geohashDecodeInt example
- Input:
{"hash" :12963433097944239317} - Output:
{"geohashDecodeInt":{"Longitude":131.03618861,"Latitude":-25.345456300000002}}
SELECT geohashDecodeInt(hash) FROM test
geohashBoundingBox example
- Input:
{"hash" :"qgmpvf18h86e"} - Output:
{"geohashBoundingBox":{"MinLat":-25.345457140356302,"MaxLat":-25.34545697271824,"MinLng":131.03619195520878,"MaxLng":131.0361922904849}}
SELECT geohashBoundingBox(hash) FROM test
geohashBoundingBoxInt example
- Input:
{"hash" :12963433097944239317} - Output:
{"geohashBoundingBoxInt":{"MinLat":-25.345456302165985,"MaxLat":-25.34545626025647,"MinLng":131.0361886024475,"MaxLng":131.03618868626654}}
SELECT geohashBoundingBoxInt(hash) FROM test
geohashNeighbor example
- Input:
{"hash" :"qgmpvf18h86e","direction":"North"} - Output:
{"geohashNeighbor":"qgmpvf18h86s"}
SELECT geohashNeighbor(hash,direction) FROM test
geohashNeighborInt example
- Input:
{"hash" :12963433097944239317,"direction":"North"} - Output:
{"geohashNeighborInt":12963433097944240129}
SELECT geohashNeighborInt(hash,direction) FROM test
geohashNeighbors example
- Input:
{"hash" :12963433097944239317} - Output:
{"geohashNeighbors":["qgmpvf18h86s","qgmpvf18h86u","qgmpvf18h86g","qgmpvf18h86f","qgmpvf18h86d","qgmpvf18h866","qgmpvf18h867","qgmpvf18h86k"]}
SELECT geohashNeighbors(hash) FROM test
geohashNeighborsInt example
- Input:
{"hash" :"qgmpvf18h86e","neber":"North"} - Output:
{"geohashNeighborsInt":[12963433097944240129,12963433097944240131,12963433097944240130,12963433097944237399,12963433097944237397,12963433097944150015,12963433097944152746,12963433097944152747]}
SELECT geohashNeighborsInt(hash) FROM test
# LabelImage plugin
This is a sample plugin to demonstrate the usage of TensorFlowLite(tflite) model interpreter. The function receives a bytea input representing an image and produce the AI label of the image by running the tflite model.
Assuming the input is the byte array of peacock.jpg, the output will be "peacock".
SELECT labelImage(self) FROM tfdemo