After slogging through lots of posts about a poorly defined request, I am left wondering if I missed the original sender properly explaining what THEY mean by a truth table and what it should look like. Some here seem to know (or are guessing) that the request is to make all combinations of TRUE and FALSE for N columns in a data.frame and some for an indefinite value of N. Some others may also want to throw in additional columns that reflect a logical AND operation and perhaps others. So I calmly request someone tell us what the real request is so I can evaluate if anything said here makes much sense in answering the real request. As I see it, if you have 2 columns, there are four possible combination in what amounts to a 4x2 matrix. If your mailer allows my text to be seen as intended, the following shows combinations starting with F, albeit a table starting with T is equivalent in terms of meaning: FFFTTFTT
For an N=3 column it gets more rows using binary notation with T=0 and F=1 so 8 rows. 000001010011100101110111 The trend becomes clear that the number of rows is 2**N power so a simple approach (albeit there are other ways shown that may be simpler to code using existing software) is to note the pattern. The first column requires 2**N items alternating every (2**N)/2 times. Meaning if N=5 then you want 32 rows in the result with 16 units of F and then 16 units of T, or vice versa. The R function that does this easily (as part of a loop perhaps) is rep() and sample code (hopefully blank lines keep it from getting wrapped funny is something like this that can be simplified: N <- 5 rows <- 2**N TF <- data.frame(index=1:rows) for (ind in rev(2**(N:1))) { TF <- cbind(TF, rep(c(TRUE, FALSE), each=rows/ind, length.out=rows)) } names(TF) <- c("index", paste("col", 1:N, sep="")) The above uses rep() repeatedly to produce runs of TRUE and FALSE of decreasing size and keeps concatenating them to an existing data.frame with cbind(). The result is a column with 16 TRUE followed by 16 FALSE then another column with 8 by 8 and repeated again as 8 by 8. The next column alternates in groups of 4 then the next in groups of two and finally alternating in "groups" of 1. Obviously this can be wrapped up in a function that takes N as an argument and makes an arbitrary N column construct with 2**N rows as described and this may be what is wanted for the main table. I threw this together rapidly and I am sure can improve it so column names are created as appropriate. For example, rather than cbind, the following would work well too: colnm <- ...TF[colnm] <- rep(c(TRUE, FALSE), each=rows/ind, length.out=rows) But the question is whether this makes what is wanted, or needs something more like columns that represent whether the OR or AND or some other boolean function of N boolean items is TRUE or FALSE. I repeat, the above analysis does not suggest other supplied solutions are bad or wrong, just a suggestion of how fairly simple functionality in R can do what is wanted. Of course, if something else is wanted, we are all wasting our time answering. I waited a while hoping not to need to or to reply to an actual question I know how to deal with. -----Original Message----- From: Jeff Newmiller <jdnew...@dcn.davis.ca.us> To: Bert Gunter <bgunter.4...@gmail.com>; Ebert, Timothy Aaron <teb...@ufl.edu> Cc: r-help@r-project.org <r-help@r-project.org>; Paul Bernal <paulberna...@gmail.com> Sent: Sun, Mar 13, 2022 5:17 am Subject: Re: [R] Is there a Truth Table Generator in R? There are 2^(2^length(tt)) possible "truth" vectors for the inputs defined in tt. AND-ing all of the inputs only gives one of those possibilities. Some popular named cases for 2 inputs are shown here [1], but it is common to use combinations of !, & and | to specify a particular truth vector. There is also the problem of reverse-engineering such a boolean expeession [2] in simplest form from a given truth vector, but I don't know if anyone has implemented such algorithms in R. [1] https://en.wikipedia.org/wiki/Truth_table [2] https://en.wikipedia.org/wiki/Karnaugh_maps On March 12, 2022 2:17:32 PM PST, Bert Gunter <bgunter.4...@gmail.com> wrote: >... >tt$truth <- tt$A & tt$B & tt$C >to evaluate the outcome of expand.grid. > >or, as I said, >tt$truth <- apply(tt,1, all) >which works for any number of columns in tt. > > >Bert Gunter > >"The trouble with having an open mind is that people keep coming along >and sticking things into it." >-- Opus (aka Berkeley Breathed in his "Bloom County" comic strip ) > >On Sat, Mar 12, 2022 at 2:02 PM Ebert,Timothy Aaron <teb...@ufl.edu> wrote: >> >> To the end of Jeff's program add >> tt$truth <- tt$A & tt$B & tt$C >> to evaluate the outcome of expand.grid. >> >> Tim >> >> -----Original Message----- >> From: R-help <r-help-boun...@r-project.org> On Behalf Of Jeff Newmiller >> Sent: Saturday, March 12, 2022 12:05 PM >> To: r-help@r-project.org; Paul Bernal <paulberna...@gmail.com>; R >> <r-help@r-project.org> >> Subject: Re: [R] Is there a Truth Table Generator in R? >> >> [External Email] >> >> both <- c( FALSE, TRUE ) >> tt <- expand.grid( C = both >> , B = both >> , A = both >> ) >> tt <- tt[, 3:1 ] >> >> On March 12, 2022 8:42:28 AM PST, Paul Bernal <paulberna...@gmail.com> wrote: >> >Dear friends, >> > >> >Hope you are doing great. I have been searching for a truth table >> >generator in R, but everything I find has a Python implementation instead. >> > >> >Maybe there is in fact a truth table generator in R, but I am not >> >searching in the right places? >> > >> >Any help and/or guidance will be greatly appreciated. >> > >> >Best regards, >> >Paul >> > >> > [[alternative HTML version deleted]] >> > >> >______________________________________________ >> >R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see >> >https://urldefense.proofpoint.com/v2/url?u=https-3A__stat.ethz.ch_mailm >> >an_listinfo_r-2Dhelp&d=DwICAg&c=sJ6xIWYx-zLMB3EPkvcnVg&r=9PEhQh2kVeAsRz >> >sn7AkP-g&m=Cj0cRxlu_GS0ARzvxm-eD27PhuhkgT_azaq1hamiYDmCglHF8_9hGTAkcDNo >> >ZtUq&s=h0wdH7OvIxKWgjwFmBIGHvswAKy8VKwyyI3IbB9dKkc&e= >> >PLEASE do read the posting guide >> >https://urldefense.proofpoint.com/v2/url?u=http-3A__www.R-2Dproject.org >> >_posting-2Dguide.html&d=DwICAg&c=sJ6xIWYx-zLMB3EPkvcnVg&r=9PEhQh2kVeAsR >> >zsn7AkP-g&m=Cj0cRxlu_GS0ARzvxm-eD27PhuhkgT_azaq1hamiYDmCglHF8_9hGTAkcDN >> >oZtUq&s=tsrpB1zmIQL_wMcn70xPEkvpaisBrAM9k2OQ8kDrebw&e= >> >and provide commented, minimal, self-contained, reproducible code. >> >> -- >> Sent from my phone. Please excuse my brevity. >> >> ______________________________________________ >> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see >> https://urldefense.proofpoint.com/v2/url?u=https-3A__stat.ethz.ch_mailman_listinfo_r-2Dhelp&d=DwICAg&c=sJ6xIWYx-zLMB3EPkvcnVg&r=9PEhQh2kVeAsRzsn7AkP-g&m=Cj0cRxlu_GS0ARzvxm-eD27PhuhkgT_azaq1hamiYDmCglHF8_9hGTAkcDNoZtUq&s=h0wdH7OvIxKWgjwFmBIGHvswAKy8VKwyyI3IbB9dKkc&e= >> PLEASE do read the posting guide >> https://urldefense.proofpoint.com/v2/url?u=http-3A__www.R-2Dproject.org_posting-2Dguide.html&d=DwICAg&c=sJ6xIWYx-zLMB3EPkvcnVg&r=9PEhQh2kVeAsRzsn7AkP-g&m=Cj0cRxlu_GS0ARzvxm-eD27PhuhkgT_azaq1hamiYDmCglHF8_9hGTAkcDNoZtUq&s=tsrpB1zmIQL_wMcn70xPEkvpaisBrAM9k2OQ8kDrebw&e= >> and provide commented, minimal, self-contained, reproducible code. >> >> ______________________________________________ >> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see >> https://stat.ethz.ch/mailman/listinfo/r-help >> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html >> and provide commented, minimal, self-contained, reproducible code. -- Sent from my phone. Please excuse my brevity. ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.