# How to enter a long logical expression into Wolfram|Alpha?

Posted 10 years ago
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 When I enter an logical expression e.g.( P && Q && R ) || ( Q && R && S )I get lots of lovely info. However, I've discovered there is a limit to the length of input e.g. ( P && Q && R && S ) || ( P && Q && R && ~S ) || ( P && Q && ~R && S ) || ( P && Q && ~R && ~S ) || ( P && ~Q && R && S ) || ( P && ~Q && R && ~S ) || ( P && ~Q && ~R && S ) || ( P && ~Q && ~R && ~S )results in a failure message, "Input Too Long! Upload as data using Data input first."When I try the data input route, I get another failure message, ""No structured data detected; performing a textual analysis instead."How do I structure or otherwise mark my input as being a single logical expression?
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Posted 8 years ago
 I don't think Mathematica struggles that much In[2]:= AbsoluteTiming[ PowerMod[078435243638422372447672231234716695757593735449641234358462086700559213667152171913, 73328617858256908828323, 1026650243044648666338779501960308972649317942706523177961403694692749456133768845419907]] Out[2]= {0.000076, 488852248312393495853898207472820633208110722640160160319617509136528516001303946959159} 
Posted 8 years ago
 Raphael, Wolfram|Alpha can't solve that kind of question. Even Mathematica would struggle to do it - your expression would take a ludicrous amount of time to compute. Probably on the order of days.The exponentiation alone is:http://www.wolframalpha.com/input/?i=078435243638422372447672231234716695757593735449641234358462086700559213667152171913^73328617858256908828360785399379915432324698 digits in length.That alone would take long enough to compute, but you're expecting a modulus operation on top of that?It's just not possible. You would need a supercomputer to calculate that result in anything resembling a "quick" time frame.
Posted 8 years ago
 It has been a year and i do not think they have fixed it. I subscribed to the pro version thinking that inputting data through files would fix the issue but it has not :( I am trying to calculate this. 078435243638422372447672231234716695757593735449641234358462086700559213667152171913^733286178582569088283232046829710496185570977121081786863578840329631292141076523731373 mod1026650243044648666338779501960308972649317942706523177961403694692749456133768845419907for an assignment and sadly it does not work. any suggetions on what i can do?
Posted 10 years ago
 For what it's worth, Simplify (or LogicalExpand) does the trick and returns P.Simplify[P&&Q&&R&&S||P&&Q&&R&&!S||P&&Q&&!R&&S||P&&Q&&!R&&!S||P&&!Q&&R&&S||P&&!Q&&R&&!S||P&&!Q&&!R&&S||P&&!Q&&!R&&!S]P
Posted 10 years ago
 Hoping that WolframAlpha will interpret precedence when I eliminate parens and white space I try each of the followingSimplify[P&&Q&&R&&S||P&&Q&&R&&~S||P&&Q&&~R&&S||P&&Q&&~R&&~S||P&&~Q&&R&&S||P&&~Q&&R&&~S]Simplify[P&&Q&&R&&S||P&&Q&&R&&~S||P&&Q&&~R&&S||P&&Q&&~R&&~S||P&&~Q&&R&&S||P&&~Q&&R&&~S||P&&~Q&&~R&&S]It happily allows me to enter both within the available line length, understands and correctly interprets the first and cannot comprehend the second.Thus I presume there is more than one internal limit on the length of input and they do not appear to be consistent.
Posted 10 years ago
 Inputing an expression as data can't be used as a way around the maximimum input length in this case.  Wolfram|Alpha will interpret anything given as data to be a dataset or a piece of text. You may want to suggest to the WolframAlpha team that they support boolean expressions as a data format in the future so that you can work with larger boolean expressions than the input bar can handle.