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Filter for first day of every year in R tidy verse

The data:

library(tidyverse)
library(tidyquant)
library(lubridate)

df <- tq_get("^GSPC", from='1930-01-01', to='2022-12-31')

I want to filter for the first date of every year.

My code:

df %>% filter(month(date) == 1, day(date) == 1) %>% head(n=Inf)

I get the following message:

A tibble: 0 x 8 … with 8 variables: symbol , date , open , high , low , close , volume , adjusted Use colnames() to see all variable names

If I use any other number than 1 in day(date) == 1 the code works.

This code works: df %>% filter(month(date) == 1, day(date) == 2) %>% head(n=Inf)

Question:

Why is day(date) == 1 not working?

Solution 
  • df %>% with(month(date) == 1 & day(date) == 1) %>% any()
> [1] FALSE

    This result shows that there isn't any observation for january first in your dataset, thus filter always returns an empty tibble. The problem is with your data, not the code.

    Another way to check it:

    df$date %>% paste() %>% grepl("[0-9]{4}-01-01", .) %>% any()
> [1] FALSE