I'm trying to make a formula and I got the error: $ operator not defined for this S4 class with R. First of all, what is a S4 class? What am I doing wrong
zenon-network
airflow-connections
php-openssl
provider-model
object-oriented-database
react-query
sqlitestudio
schemacrawler
video-embedding
react-material-ui-carousel
bitmex
jaeger-client-go
jsx
xcode11.2.1
webpack-serve
powerbi-custom-visuals
perfect-scrollbar
internal-load-balancer
ready-api
devextreme-angular
inkml
uiautomatorviewer
sfinae
es6-promise
lightopenid
api-key
defunct
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abcpdf
integer-promotion
