Andrew Simmons
2022-Oct-24 16:28 UTC
[R] When using require(), why do I get the error message "Error in if (!loaded) { : the condition has length > 1" ?
require(), similarly to library(), does not evaluate its first argument UNLESS you add character.only = TRUE require( packages_i_want_to_use[1], character.only = TRUE) On Mon, Oct 24, 2022, 12:26 Kelly Thompson <kt1572757 at gmail.com> wrote:> # Below, when using require(), why do I get the error message "Error > in if (!loaded) { : the condition has length > 1" ? > > # This is my reproducible code: > > #create a vector with the names of the packages I want to use > packages_i_want_to_use <- c('base', 'this_pac_does_not_exist') > > # Here I get error messages: > require( packages_i_want_to_use[1] ) > #Error in if (!loaded) { : the condition has length > 1 > > require( packages_i_want_to_use[2] ) > #Error in if (!loaded) { : the condition has length > 1 > > # Here I get what I expect: > require('base') > > require('this_pac_does_not_exist') > #Loading required package: this_pac_does_not_exist > #Warning message: > #In library(package, lib.loc = lib.loc, character.only = TRUE, > logical.return = TRUE, : > # there is no package called ?this_pac_does_not_exist? > > ______________________________________________ > R-help at 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]]
Kelly Thompson
2022-Oct-24 16:42 UTC
[R] When using require(), why do I get the error message "Error in if (!loaded) { : the condition has length > 1" ?
Thanks! # Please, can you help me understand why require( 'base' ) # works, but require( packages_i_want_to_use[1] ) # does not work? # In require( 'base' ), what is the "first argument"? On Mon, Oct 24, 2022 at 12:29 PM Andrew Simmons <akwsimmo at gmail.com> wrote:> > require(), similarly to library(), does not evaluate its first argument UNLESS you add character.only = TRUE > > require( packages_i_want_to_use[1], character.only = TRUE) > > > On Mon, Oct 24, 2022, 12:26 Kelly Thompson <kt1572757 at gmail.com> wrote: >> >> # Below, when using require(), why do I get the error message "Error >> in if (!loaded) { : the condition has length > 1" ? >> >> # This is my reproducible code: >> >> #create a vector with the names of the packages I want to use >> packages_i_want_to_use <- c('base', 'this_pac_does_not_exist') >> >> # Here I get error messages: >> require( packages_i_want_to_use[1] ) >> #Error in if (!loaded) { : the condition has length > 1 >> >> require( packages_i_want_to_use[2] ) >> #Error in if (!loaded) { : the condition has length > 1 >> >> # Here I get what I expect: >> require('base') >> >> require('this_pac_does_not_exist') >> #Loading required package: this_pac_does_not_exist >> #Warning message: >> #In library(package, lib.loc = lib.loc, character.only = TRUE, >> logical.return = TRUE, : >> # there is no package called ?this_pac_does_not_exist? >> >> ______________________________________________ >> R-help at 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.