error in put vertical buying power calculation

[bayareacoder]

I believe the buying power (margin) requirement for a short vertical in putVertical.py, shown as:
buyingPower = ((self.__putToSell.strikePrice - self.__putToBuy.strikePrice) - ( currentPutToSellPrice - currentPutToBuyPrice)) * self.__numContracts * 100

is not correct. It should be just the width of the spread * 100 * number of contracts as that is the max value it could achieve if the short spread is fully in the money. So:
buyingPower = (self.__putToSell.strikePrice - self.__putToBuy.strikePrice) * self.__numContracts * 100

UPDATE: OK I guess they allow the credit received to count against the margin requirement. That could be specific to Tastytrade. Then it's correct.
https://support.tastytrade.com/support/s/solutions/articles/43000435260

[sirnfs]

I believe this is correct. Can you please check the explanation and example here: https://tastytrade.com/learn/options/short-put-vertical-spread/

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On Tue, Jun 25, 2024, 6:24 AM B ***@***.***> wrote: I believe in putVertical.py: buyingPower = ((self.__putToSell.strikePrice - self.__putToBuy.strikePrice) - ( currentPutToSellPrice - currentPutToBuyPrice)) * self.__numContracts * 100 should be: buyingPower = ((self.__putToSell.strikePrice - self.__putToBuy.strikePrice) * ( currentPutToSellPrice - currentPutToBuyPrice)) * self.__numContracts * 100 - should be * — Reply to this email directly, view it on GitHub <#14>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AB6QJ4KRRN2MKFUZS2WBCKDZJDWINAVCNFSM6AAAAABJ3AL3U6VHI2DSMVQWIX3LMV43ASLTON2WKOZSGM3TCNRRGQ2TINY> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[bayareacoder]

Yes it is correct as mentioned in my update. But when you do iron condors (vertical put & call spread) then it's not so simple as now the margin requirement of a put vertical depends on matching call verticals in the portfolio.
Have you done code for an iron condor (i.e. matching put + call short verticals) strategy?

[sirnfs]

I don't have code for an iron condor, but here's how the buying power is calculated with Tastytrade: https://support.tastytrade.com/support/s/solutions/articles/43000435229

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On Tue, Jun 25, 2024, 5:46 PM B ***@***.***> wrote: Yes it is correct as mentioned in my update. But when you do iron condors (vertical put & call spread) then it's not so simple as now the margin requirement of a put vertical depends on matching call verticals in the portfolio. Have you done code for an iron condor (i.e. matching put + call short verticals) strategy? — Reply to this email directly, view it on GitHub <#14 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AB6QJ4PKTA3PXFGFDXJOOKDZJGGENAVCNFSM6AAAAABJ3AL3U6VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDCOBZGMYDMOJRGQ> . You are receiving this because you commented.Message ID: ***@***.***>

[sirnfs]

Note that I actually checked and and confirmed this on the Tastytrade platform.

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On Tue, Jun 25, 2024, 6:19 PM Michael Santoro ***@***.***> wrote: I don't have code for an iron condor, but here's how the buying power is calculated with Tastytrade: https://support.tastytrade.com/support/s/solutions/articles/43000435229 On Tue, Jun 25, 2024, 5:46 PM B ***@***.***> wrote: > Yes it is correct as mentioned in my update. But when you do iron condors > (vertical put & call spread) then it's not so simple as now the margin > requirement of a put vertical depends on matching call verticals in the > portfolio. > Have you done code for an iron condor (i.e. matching put + call short > verticals) strategy? > > — > Reply to this email directly, view it on GitHub > <#14 (comment)>, > or unsubscribe > <https://github.com/notifications/unsubscribe-auth/AB6QJ4PKTA3PXFGFDXJOOKDZJGGENAVCNFSM6AAAAABJ3AL3U6VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDCOBZGMYDMOJRGQ> > . > You are receiving this because you commented.Message ID: > ***@***.***> >

[sirnfs]

Going to go ahead and close this issue. Thanks for reviewing the code.