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https://issues.apache.org/jira/browse/ARROW-15665?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17506955#comment-17506955
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Dragoș Moldovan-Grünfeld commented on ARROW-15665:
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I will ask the question here and move it if it is the wrong place / follow-up
Jira required. In R {{strptime}} returns NA / NULL in the following
circumstances:
# 1 {{format}} doesn't match {{string}} - e.g. {{"1999-12-31" and "%Y-%d-%M"}}
# 2 {{string}} doesn't make sense, given the format - e.g. {{string}} is
{{"this is a string that doesn't make sense"}}
# 3 the {{string}} can be parsed with the given {{format}}, but implicitly
relies on rollover - {{string}} is {{"1999-02-30"}} and is parsed as the
{{"1999-03-02"}} Date.
not sure 1 and 2 are actually different, but the 3rd part is different from the
current Arrow behaviour
{code:r}
library(arrow, warn.conflicts = FALSE)
library(lubridate, warn.conflicts = FALSE)
library(dplyr, warn.conflicts = FALSE)
df <- tibble::tibble(string_date = "1999-02-30")
df %>%
mutate(date = strptime(string_date, format = "%Y-%m-%d"))
#> # A tibble: 1 × 2
#> string_date date
#> <chr> <dttm>
#> 1 1999-02-30 NA
df %>%
arrow_table() %>%
mutate(date = strptime(string_date, format = "%Y-%m-%d")) %>%
collect()
#> # A tibble: 1 × 2
#> string_date date
#> <chr> <dttm>
#> 1 1999-02-30 1999-03-02 00:00:00
{code}
How are things done in Python? Does the R behaviour align with your
expectations / Is it breaking any ISO Standard?
> [C++] Add error handling option to StrptimeOptions
> --------------------------------------------------
>
> Key: ARROW-15665
> URL: https://issues.apache.org/jira/browse/ARROW-15665
> Project: Apache Arrow
> Issue Type: Improvement
> Components: C++
> Reporter: Rok Mihevc
> Assignee: Rok Mihevc
> Priority: Major
> Labels: kernel, pull-request-available
> Time Spent: 40m
> Remaining Estimate: 0h
>
> We want to have an option to either raise, ignore or return NA in case of
> format mismatch.
> See
> [pandas.to_datetime|https://pandas.pydata.org/docs/reference/api/pandas.to_datetime.html]
> and lubridate
> [parse_date_time|https://lubridate.tidyverse.org/reference/parse_date_time.html]
> for examples.
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