@danny.mullins1

There's no difference in the behavior between Eikon Data APIs and =TR function in Excel. The difference is in the parameters you use. In your get_data call you specified FRQ as a field level parameter. In your =TR function you specified it as a request level parameter. If in your =TR function you specify FRQ as a field level parameter, the function will return "Invalid value for Frq parameter". Try

=TR("PEI.N","TR.F.NetOpIncNOITot(SDate=2020-01-01,EDate=1D,Frq=CW)")

There's no weekly data for TR.F.NetOpIncNOITo. Adding FRQ=CW to the request level parameter will merely result in the same fiscal interim or fiscal year figure (depending on the value of Period parameter) being repeated for every calendar week between SDate and EDate. If this is indeed the outcome you were going for, then try

ek.get_data(['PEI.N'], ['TR.F.NetOpIncNOITot.date',
                        'TR.F.NetOpIncNOITot.calcdate',
                        'TR.F.NetOpIncNOITot'], 
            {'SDate':'2020-01-01', 'EDate':'1D', 'Period':'FI0', 'Frq':'CW'} )

Hi @danny.mullins1

I confirm that I received the same error for both fields.

However, this forum is not the best place to ask about content(fields/parameters) questions.
For an authoritative answer to any content questions, the best resource is the Refinitiv Content Helpdesk.
This forum is dedicated to things specific to the use of Eikon APIs.
The moderators here do not have deep expertise in every type of content available through Eikon.
The Refinitiv Content Helpdesk can be reached using Contact Us capability in your Eikon application.
Or by calling the Helpdesk number in your country.
Or at https://my.refinitiv.com/

Hi thanks for the response - I asked the question here because the same fields are executable within excel using that frequency and parameters, so wondered why this is not the same for the API? I will raise this with the content team anyway.

Could you please maybe assist in how I can transform a daily series of that metrics so it only takes a snapshot weekly of the daily series (proxy for the calendar week option not being available). I understand this may not be possible but thought I would ask.

Best,

Danny