Your original problem statement seemed to me to be one of wanting to
transform all the lower case identifiers to upper except for pmin and
pmax. My suggestion was not to bother and transform everything and then
define PMIN and PMAX.
On 28/02/2015 14:34, Alrik Thiem wrote:
Dear Michael
I'm not sure how you mean this. Maybe a more general description of my problem
is helpful for clarifying.
What I have to deal with are truth table output functions that always take, for
example, the following form:
Delta <- "(a*B+a*C*d<=>Y)*(E+e)"
I.e. these functions will always have the structure (.*.+.*.+...<=>.)*(.+.), where the
dots in the antecedent could be further conjunctions of unspecified complexity. I now need to
filter all rows from the truth table that are compatible with this output function. To create
the input part of the truth table "tt" for Delta above, I do:
library(QCA) # createMatrix() function is part of this package
Delta.upper <- toupper(Delta)
f.names <- unique(unlist(strsplit(Delta.upper, "[(*+<=>)]")))
f.names <- f.names[f.names != ""]
tt <- data.frame(createMatrix(rep(2, length(f.names))))
dimnames(tt) <- list(as.character(seq(2^length(f.names))), f.names)
tt
tt
A B C D Y E
1 0 0 0 0 0 0
2 0 0 0 0 0 1
. . . . . . .
63 1 1 1 1 1 0
64 1 1 1 1 1 1
I now need to transform Delta into a string of the following form in order to extract the
subset of compatible rows from "tt":
"pmin(pmax(pmin(1-tt$A,tt$B),pmin(1-tt$A,tt$C,1-tt$D))==tt$Y,pmax(tt$E,1-tt$E))==TRUE"
With this string, I can then do:
tt[pmin(pmax(pmin(1-tt$A,tt$B),
pmin(1-tt$A,tt$C,1-tt$D))==tt$Y,pmax(tt$E,1-tt$E))==TRUE, ]
A B C D Y E
1 0 0 0 0 0 0
2 0 0 0 0 0 1
. . . . . . .
61 1 1 1 1 0 0
62 1 1 1 1 0 1
-----Ursprüngliche Nachricht-----
Von: Michael Dewey [mailto:i...@aghmed.fsnet.co.uk]
Gesendet: Samstag, 28. Februar 2015 14:50
An: Alrik Thiem
Cc: r-help@r-project.org
Betreff: Re: [R] Substring replacement in string
Dear Alrik
This may seem a silly suggestion but why not just define new functions
PMIN and PMAX to call pmin and pmax. Obviously that does not solve your
problem if it is more general than your example.
On 28/02/2015 13:16, Alrik Thiem wrote:
Dear Gabor,
Many thanks. Works like a charm, but I can't get it to work with
"pmin(pmax(pmin(a,B),pmin(a,C,d))==Y,pmax(E,e))"
i.e., with strings where there're no integers following the components in the
pmin/pmax functions. Could this be generalized to handle both cases?
Best wishes,
Alrik
-----Ursprüngliche Nachricht-----
Von: Gabor Grothendieck [mailto:ggrothendi...@gmail.com]
Gesendet: Samstag, 28. Februar 2015 13:35
An: Alrik Thiem
Cc: r-help@r-project.org
Betreff: Re: [R] Substring replacement in string
On Fri, Feb 27, 2015 at 5:19 PM, Alrik Thiem <alrik.th...@gmail.com> wrote:
I would like to replace all lower-case letters in a string that are not part
of certain fixed expressions. For example, I have the string:
"pmin(pmax(pmin(x1, X2), pmin(X3, X4)) == Y, pmax(Z1, z1))"
Where I would like to replace all lower-case letters that do not belong to
the functions "pmin" and "pmax" by 1 - toupper(...) to get
"pmin(pmax(pmin(1 - X1, X2), pmin(X3, X4)) == Y, pmax(Z1, 1 - Z1))"
Assuming x is the input string:
gsub("(\\b[a-oq-z][a-z0-9]+)", "1-\\U\\1", x, perl = TRUE)
## [1] "pmin(pmax(pmin(1-X1, X2), pmin(X3, X4)) == Y, pmax(Z1, 1-Z1))"
--
Michael
http://www.dewey.myzen.co.uk
______________________________________________
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.
