Display step signal projected before new data point

[Bayden Smith]

Hi,

 

We have data displayed in Seeq that represents a physical sample result collected and tested.  This result is assumed to be representative of the time period from the previous sample result up until the last sample result.

When displaying this data in Seeq as a step signal the step change occurs such that the sample result is shown from the new sample point going forwards.

Currently I do this by getting the data from its source and manually manipulating the data point times using excel and then importing to Seeq via CSV to get it to display correctly.

Is there anyway to have this display going backwards to the previous sample within Seeq?  The sample times are not consistent, so it is not possible to just move the signal by a fixed amount.  Other software packages I have used previously have the ability to display the step as either before or after the new data point (such as P2 Explorer).

The example below shows my manipulated data (green trend line) compared to the connected data source data (orange trend line).  i.e. need to make orange line display as green line.

[Thorsten Vogt]

Hello,

you can achieve this using a transform. The following formula uses a transform to iterate over the samples and puts the value of the current sample on the timestamp of the previous sample:

$signal.transform(
  ($previous, $current) -> sample(
      $previous.key(),
      $current.value()
    )
  )

The image below shows the result according to your screenshot (original signal on second lane, shifted signal on first lane):

Regards,

Thorsten

[Bayden Smith]

Thank you, that is perfect!