r - How to properly return character values for dplyr's do? -


consider following code:

foo <- function() {   if (runif(1) < 0.5) {     return(data.frame(result="low"))   } else {     return(data.frame(result="high"))   } }  df = data.frame(val=c(1,2,3,4,5,6)) df %>% group_by(val) %>% do(foo())

it random, if there both "low" , "high" results returned, you'll see errors this:

warning messages: 1: in bind_rows_(x, .id) : unequal factor levels: coercing character 2: in bind_rows_(x, .id) :   binding character , factor vector, coercing character vector 3: in bind_rows_(x, .id) :   binding character , factor vector, coercing character vector 4: in bind_rows_(x, .id) :   binding character , factor vector, coercing character vector 5: in bind_rows_(x, .id) :   binding character , factor vector, coercing character vector

i believe first value being returned (say, "low") converted factor 1 level, , when other level comes along, incurs dplyr's wrath.

what proper way code example avoid warnings?

edit: 1 solution this:

foo <- function() {   if (runif(1) < 0.5) {     return(data.frame(result=factor("low", levels=c("low", "high"))))   } else {     return(data.frame(result=factor("high", levels=c("low", "high"))))   } }

but if don't know factor levels ahead of time?

also, more fundamentally, i'd return character vector, not factor.

either:

  • use stringsasfactors=false: return(data.frame(..., stringsasfactors=false))

or:

  • use data_frame: return(data_frame(...))

see ?data.frame more factor treatment.


Comments

Post a Comment

Popular posts from this blog

PHP and MySQL WP -

i trying accomplish 2 things here code. writing php directly wp page using insert php plugin. 1) query mysql database , return results 1 column 4 columns. 2) make each result own hyperlink directs user new wp page runs new query on page. i able query show results , turn results dynamic hyperlink, cannot formatting down. right returns result 1 column. here have: [insert_php] $servername = "localhost"; $username = "login"; //edited privacy $password = "password"; //edited privacy $database = "database"; //edited privacy // create connection $conn = new mysqli($servername, $username, $password, $database); // check connection if ($conn->connect_error) { die("connection failed: " . $conn->connect_error); } echo "connected successfully"; //get results database $result = mysqli_query($conn,"select mine mines order mine"); $all_property = array(); //declare array saving property //showing proper...
Read more

android - InAppBilling registering BroadcastReceiver in AndroidManifest -

i'm implementing inapp billing in android app. works well, however, i'm trying decouple broadcast receiver activity manifest. suggestion in android's trivialdrive sample: // important: dynamically register broadcast messages updated purchases. // register receiver here instead of <receiver> in manifest // because call getpurchases() @ startup, therefore can ignore // broadcasts sent while app isn't running. // note: registering listener in activity bad idea, done here // because sample. regardless, receiver must registered after // iabhelper setup, before first call getpurchases(). currently there's class extends broadcastreceiver : public class iabbroadcastreceiver extends broadcastreceiver { /** * intent action receiver should filter for. */ public static final string action = "com.android.vending.billing.purchases_updated"; private final iabbroadcastlistener mlistener; public iabbroadcastreceiver(iabbroadcastlistener listener) { m...
Read more

nginx - phpPgAdmin - log in works but I have to login again after clicking on any links -

i have setup postgres 9.6 , phppgadmin on centos 7 server nginx, i can log in phppgadmin, postgresql server on right of page remains crossed out , link try browse (databases, roles etc) requires log in again. i'm thinking seems sessions problem, unsure how resolve it. any pointers on how fix or should looking @ in order track down problem? solved. turns out owner of /var/lib/php/session apache - needed nginx. sorted changing ownership nginx below: chown -r nginx:nginx /var/lib/php/session/
Read more