[R] Identifying column type

[Jeff Newmiller]

Does

sapply( mydata, inherits, what = "POSIXt" )

give you any ideas?

On April 9, 2021 8:25:36 PM PDT, Steven Yen <styen using ntu.edu.tw> wrote:
>I have data of mixed types in a data frame - date and numeric, as shown
>
>in summary below. How do I identify the column(s) that is/are not 
>numeric, in this case, the first. All I want is to identify the 
>column(s) and so that I can remove it/them from the data frame Thanks.
>
>> summary(mydata)
>
>Date Spot Futures Min. :1997-09-01 00:00:00 Min. : 735.1 Min. : 734.2 
>1st Qu.:2002-10-16 12:00:00 1st Qu.:1120.7 1st Qu.:1122.6 Median 
>:2007-12-01 00:00:00 Median :1301.8 Median :1303.2 Mean :2007-12-01 
>06:01:27 Mean :1423.1 Mean :1423.6 3rd Qu.:2013-01-16 12:00:00 3rd 
>Qu.:1540.0 3rd Qu.:1546.5 Max. :2018-03-01 00:00:00 Max. :2823.8 Max. 
>:2825.8
>
>
>	[[alternative HTML version deleted]]
>
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-- 
Sent from my phone. Please excuse my brevity.