I want an IF operator in Charts.

Hi ​@Shun Takase!

Thank you for suggesting this product idea. We will follow the traction this idea gets in the community. You can expect updates on this post if we decide to include this in our future roadmap, or if we require more information.

Hi, ​@Jørgen Lund !

Thank you for your reply.
 I hope there will be progress on this feature in the future.

Another option to achieve this same behavior might be to implement IFs and Logic ops in Synthetic Time Series and have a way to reference a synthetic time series calculation in Charts. I to very often need to make calculations after verfying “stable state”; i.e. Machine in operation for 2 hours & | SP - PV | < 10 degrees & ... 

Hi ​@Shun Takase!

The functionality you are looking for is already available using a block called “Logical Check”.

This is the block description: “Perform a logical check between time series/constants and returns the assigned time series/constants when the condition holds true or false. The logical check is performed following the format: Value 1 {operator} Value 2, where the operator can be Equality (==), Inequality (!=), Greater than (>), Greater or equal than (>=), Smaller than (<) or Smaller or equal than (<=).”

Here’s a simple example.

Hi , ​@APSHANKAR Sagar !

Thank you for your reply.
Is my understanding correct that a Synthetic Time Series is something calculated outside of Charts, 
then registered in the CDF as a time series and used from there?
Apologies if I’m off the mark.
 

Hi , ​@Everton Colling  !
Thank you for your reply.

Thank you also for sharing such a great idea, and for the clear example.
I wasn’t aware of this operator, but it looks like it could be used in many ways similar to an IF operator.
I’ll go ahead and share this internally and start using it right away.

Hi Shun, AFAIK, an STS is not ‘registered’ in CDF, but calculated on the fly. It helps you make calculations using multiple time series. Every time you want to see it, you call it with your expression. Here is an example.

 

variables = {"SP": set_point_ts_ext, "PV": process_val_ts_ext}

    expression_pv = ["PV"]
    if limit_type == 'Percentage':
            expression_sp = [f"SP * {1 - lcl/100}" , f"SP * {1 + ucl/100}" ]
    elif limit_type == 'Relative':
            expression_sp = [f"SP - {lcl}" , f"SP + {ucl}"]
    else:
        logger.error(f"Unknown limit type {limit_type}.")
        return

    pv_df = client.time_series.data.synthetic.query(expressions=expression_pv, start=start_time, end='now', 
                                                    granularity = '1m', aggregate = 'average',
                                                    variables=variables,
                                                    ).to_pandas()

Hi , ​@APSHANKAR Sagar  !
Thank you for your reply.

I see — I understand the idea now, and I really appreciate the clear example you provided.
Since this involves using the API, it seems like some technical skill is required to handle it properly,
but it looks like this approach can cover most of the processing I want to achieve!
I’ll definitely give it a try.