Writing loops in R to loop over functions

The below vector is used to loop over 3 columns that I want to cross tabulate against sexual identity:


```{r}
l=c("nationality", "sex_at_birth", "education")
for (i in l){
 mytables<-table(HIV_coded$sexual_identity, HIV_coded[,i])
 print(mytables)
 } 
 ```

The below loop is used to calculate the summary statistics for a series of variables:
```
l=c("age", "age_1")
for (i in l) {
  mymeans<-summary(HIV_coded[,i])
  print(mymeans)
}
```

Introduction to the Analysis of Survival Data in the Presence of Competing Risks

 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4741409/