FB_ALY_DynamicTimeWarpingInterval
The Dynamic Time Warping Interval algorithm compares several input data with each other. The special feature of the algorithm is that signals with different speeds or even shifted signals can be compared. Only the signal interval of a configured window is considered for the comparison. New results are output after the window expires. As a result, the distance between the reference signal and the respective input signal is output. The smaller the distance, the more equal the compared signals are. If the distance is 0, both signals are identical. The amount of distance depends on the equality but also on the length of the signals.
Syntax
Definition:
FUNCTION_BLOCK FB_ALY_DynamicTimeWarpingInterval
VAR_OUTPUT
ipResultMessage: Tc3_EventLogger.I_TcMessage;
bError: BOOL;
bNewResult: BOOL;
bConfigured: BOOL;
nBestMatchIdx: UDINT;
END_VAR
Outputs
Name | Type | Description |
|---|---|---|
ipResultMessage | Contains more detailed information on the current return value. This special interface pointer is internally secured so that it is always valid/assigned. | |
bError | BOOL | This output is |
bNewResult | BOOL | When a new result has been calculated, the output is |
bConfigured | BOOL | Displays |
nBestMatchIdx | UDINT | Outputs the index of the input channel with the smallest distance to the reference channel. |
Methods
Name | Definition location | Description |
|---|---|---|
Call() | Local | Method for calculating the outputs for a specific configuration. |
Configure() | Local | Configuration of the algorithm. |
FB_init() | Local | Initializes the number of input channels. |
GetChannelOutputVaue() | Local | Method for getting individual output values from the output array |
GetChannelOutputArray() | Local | Method for getting the entire output array. |
Reset() | Local | Resets all internal states or the calculations performed so far. |
SetChannelValue() | Local | Method for passing values to the algorithm. |
Sample
VAR
fbDynamicTimeWarpingInterval : FB_ALY_DynamicTimeWarpingInterval(nNumChannels := 3);
nWindowSize : UDINT := 100;
bConfigure : BOOL := TRUE;
fReference : LREAL;
fInput1 : LREAL;
fInput2 : LREAL;
fInput3 : LREAL;
aDistances : ARRAY[1..3] OF LREAL;
END_VAR
// Configure algorithm
IF bConfigure THEN
bConfigure := FALSE;
fbDynamicTimeWarpingInterval.Configure(nWindowSize);
END_IF
// Call algorithm
fbDynamicTimeWarpingInterval.SetChannelValue(0, fReference);
fbDynamicTimeWarpingInterval.SetChannelValue(1, fInput1);
fbDynamicTimeWarpingInterval.SetChannelValue(2, fInput2);
fbDynamicTimeWarpingInterval.SetChannelValue(3, fInput3);
fbDynamicTimeWarpingInterval.Call();
// Get results
fbDynamicTimeWarpingInterval.GetOutputArray(pArrayOut:=ADR(aDistances), nArrayOutSize:=SIZEOF(aDistances));
Requirements
Development environment | Target platform | Plc libraries to include |
|---|---|---|
TwinCAT v3.1.4024.0 | PC or CX (x64, x86) | Tc3_Analytics |