[R] Identifying column type

[Steven Yen]

Thanks much! Yes it does. I will read.

On 2021/4/10 上午 11:33, Jeff Newmiller wrote:
> 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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