c# - Any way to replicate the OR operator with only ANDs? -


so trying find way allow or operations on front-end of app , translate condition on back-end server talk intrinio (financial data api). endpoint trying use (to save on api call credits) allows , operator hoping there sort of way around this.

here endpoint trying use: http://docs.intrinio.com/#securities-search-screener

here example condition sending server translated:

open_price > 10 && (current_volume > 1000000 || current_volume > average_volume)

p.s open_price, current_volume, , average_volume tags used within intrinio ecosystem

i should mention don't have nots

i implore guys @ link before commenting...

in general, can't.

in api, can negate atomic conditions only, changing ~gt~ ~lte~ etc., e. g. changing open_price~gt~10 open_price~lte~10.

but can't negate non-atomic conditions in api, in particular can't use de morgan's laws.

there 3n (+1) boolean functions of n variables, expressible using conjunction , atomic negation. total number of boolean functions of n variables 22ⁿ. way, of them expressible using conjunction , non-atomic negation. thus, there exist boolean functions not expressible using conjunction , atomic negation.

you should make 2 or more requests , union results on api client. there few ways differ in number of requests, in total number of records retrieved (some records might retrieved more once), , in api call credits required (it equal number of conditions).

let's suppose original data looks follows (let's skip open_price attribute).

{   {    "identifier": "a-ok",    "current_volume": 1000002, "average_volume": 1000001   },   {    "identifier": "b-ok",    "current_volume": 1000001, "average_volume":  999999   },   {    "identifier": "d-ok",    "current_volume":  999999, "average_volume":  999998   },   {    "identifier": "e-ok",    "current_volume": 1000001, "average_volume": 1000002   },   {    "identifier": "g-no",    "current_volume":  999999, "average_volume": 1000001   },   {    "identifier": "h-no",    "current_volume":  999998, "average_volume":  999999   } }

you need retrieve records identifiers a-ok, b-ok, d-ok, e-ok.

approach 1 (two requests, resultsets not disjoint)

current_volume~gt~1000000 current_volume~gt~average_volume

as can see, perform disjunction on client, not on server...

approach 2 (three requests, resultsets disjoint)

current_volume~gt~1000000,current_volume~gt~average_volume current_volume~gt~1000000,current_volume~lte~average_volume current_volume~lte~1000000,current_volume~gt~average_volume

in approach, rely on fact: a||b equal (a && b) ^^ (a && !b) ^^ (!a && b).

approach 3 (two requests, resultsets disjoint)

current_volume~gt~1000000 current_volume~lte~1000000,current_volume~gt~average_volume

in approach, rely on fact: a||b equal a ^^ (!a && b).

approach 4 (two requests, resultsets disjoint)

in particular case, there exists approach relies on transitivity of order relation on real numbers.

average_volume~gt~1000000,current_volume~gt~1000000 average_volume~lte~1000000,current_volume~gt~average_volume

however, approach not give profit in terms of api call credits.

comparison

+----------+----------+-----------+--------------+----------+ | approach | number of| records   | resultsets   | total    | |          | requests | retrieved | disjointness | credits  | +----------+----------+-----------+--------------+----------+ |  # 1     |    2     |   6 (3+3) |    no        |    2     | |  # 2     |    3     |   4       |    yes       |    6     | |  # 3     |    2     |   4       |    yes       |    3     | |  # 4     |    2     |   4       |    yes       |    4     | +----------+----------+-----------+--------------+----------+

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