How to add new column in R during for loop?

Question

I wanted to find the age in the database, I used this answer to solve the problem Get the difference between dates in terms of weeks, months, quarters, and years?

This code I used to find years

age <- function(dob, age.day = today(), units = "years", floor = TRUE) {
  calc.age = interval(dob, age.day) / duration(num = 1, units = units)
  if (floor) return(as.integer(floor(calc.age)))
  return(calc.age)
}

But when I am performing loop using for loop and trying to save value in new column in database customer, I am not able to do so.

for (i in customer$dateofbirth) {
  as.Date(i)
  customer$age <- age(i)
}

The result I am getting is same value in age column. Where I am going wrong?

Please read the info about [how to ask a good question](http://stackoverflow.com/help/how-to-ask) and how to give a [reproducible example](http://stackoverflow.com/questions/5963269). This will make it much easier for others to help you. — zx8754, Jul 18 '16 at 07:42
I understand but I am doing course where they share there database in remote computer with no internet access. I will try to edit my question as much as I can. — Hassan Qamar, Jul 18 '16 at 08:04

user2100721 · Answer 1 · 2016-07-18T06:50:26.040

2

If you want to use for loop, maybe this is helpful

for (i in customer$dateofbirth) 
 customer$age[i] <- age(as.Date(i))

@RHertel thanks for the comment age(as.Date(i))

edited Jul 18 '16 at 06:50

answered Jul 18 '16 at 06:29

user2100721

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@RHertel : Thanks for the comment. I overlooked that. – user2100721 Jul 18 '16 at 06:53
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You're welcome. I'm not sure that this works, though. The OP hasn't provided a reproducible example. – RHertel Jul 18 '16 at 06:55

Maiasaura · Accepted Answer · 2016-07-18T06:49:47.217

1

library(dplyr)
customer <- customer %>%
  rowwise() %>% 
  mutate(age = age(as.Date(dateofbirth)))

edited Jul 18 '16 at 06:49

answered Jul 18 '16 at 06:27

Maiasaura

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Its coming "character string is not in a standard umambigious format" – Hassan Qamar Jul 18 '16 at 07:42
It's not possible to troubleshoot further without some example data. See the comment in your question. – Maiasaura Jul 18 '16 at 07:44

How to add new column in R during for loop?

2 Answers2

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