[R] Comparing 2 dale columns

PIKAL Petr petr.pikal at precheza.cz
Thu Aug 24 11:17:41 CEST 2017


Hm.

I used the code from Mark's response and it works correctly. So you either messed the data or you do not tell us the whole story.

data
> dput(data)
structure(list(COL1 = structure(c(16222, 16252), class = "Date"),
    COL2 = structure(c(16556, 16556), class = "Date"), Date_Flag = c(0,
    0)), .Names = c("COL1", "COL2", "Date_Flag"), row.names = c(NA,
-2L), class = "data.frame")

Instead of ifelse you can use

data$Date_Flag_calc <- (data$COL2 < data$COL1)*1
data
        COL1       COL2 Date_Flag Date_Flag_calc
1 2014-06-01 2015-05-01         0              0
2 2014-07-01 2015-05-01         0              0


What is result of

str(data)
in your case?


Cheers
Petr

From: Patrick Casimir [mailto:patrcasi at nova.edu]
Sent: Wednesday, August 23, 2017 6:10 PM
To: PIKAL Petr <petr.pikal at precheza.cz>; r-help at r-project.org
Subject: Re: Comparing 2 dale columns




Thanks. But when I apply your codes I get all NA instead of TRUE and FALSE

________________________________
From: PIKAL Petr <petr.pikal at precheza.cz<mailto:petr.pikal at precheza.cz>>
Sent: Wednesday, August 23, 2017 11:20:00 AM
To: Patrick Casimir; r-help at r-project.org<mailto:r-help at r-project.org>
Subject: RE: Comparing 2 dale columns

Hi

your code is wrong.

I get
> test<-read.table("clipboard", header=T)
> str(test)
'data.frame':   2 obs. of  2 variables:
 $ COL1: Factor w/ 2 levels "6/1/14","7/1/14": 1 2
 $ COL2: Factor w/ 1 level "5/1/15": 1 1
> test$COL2<- as.Date(as.character(test$COL2, format="%y/%m/%d"))
> test$COL1<- as.Date(as.character(test$COL1, format="%y/%m/%d"))
                                                                                 ^^^^^^^^^^^^^^^^^^^^^^^
incorrect parentheses position, wrong y,m,d

Using correct syntax I get correct result.

> test$COL2<- as.Date(test$COL2, format="%d/%m/%y")
> test$COL1<- as.Date(test$COL1, format="%d/%m/%y")
>
> test$COL2 > test$COL1
[1] TRUE TRUE
> test
        COL1       COL2
1 2014-01-06 2015-01-05
2 2014-01-07 2015-01-05
>

Cheers
Petr

> -----Original Message-----
> From: R-help [mailto:r-help-bounces at r-project.org] On Behalf Of Patrick
> Casimir
> Sent: Wednesday, August 23, 2017 4:54 PM
> To: r-help at r-project.org<mailto:r-help at r-project.org>
> Subject: [R] Comparing 2 dale columns
>
> Dear R fellows,
>
>
> I created a new column Date_flag to compare the dates of COL1 and COL2
> using the code below. But it showed that 5/1/15 is greater than 6/1/2014 and
> 5/1/2015 greater than
> 7/1/2014 despite the year is greater. How do I fix that? I did try to format as
> %y/%m/%d
>
>  but it does not fix that.
>
>
> data$Date_Flag <- ifelse(data$COL2 > data$COL1, 0,1)
>
>
> COL1       COL2
> 6/1/14     5/1/15
> 7/1/14     5/1/15
>
>
> data$COL2<- as.Date(as.character(data$COL2, format="%y/%m/%d"))
> data$COL1<- as.Date(as.character(data$COL1, format="%y/%m/%d"))
>
>

________________________________
Tento e-mail a jak?koliv k n?mu p?ipojen? dokumenty jsou d?v?rn? a jsou ur?eny pouze jeho adres?t?m.
Jestli?e jste obdr?el(a) tento e-mail omylem, informujte laskav? neprodlen? jeho odes?latele. Obsah tohoto emailu i s p??lohami a jeho kopie vyma?te ze sv?ho syst?mu.
Nejste-li zam??len?m adres?tem tohoto emailu, nejste opr?vn?ni tento email jakkoliv u??vat, roz?i?ovat, kop?rovat ?i zve?ej?ovat.
Odes?latel e-mailu neodpov?d? za eventu?ln? ?kodu zp?sobenou modifikacemi ?i zpo?d?n?m p?enosu e-mailu.

V p??pad?, ?e je tento e-mail sou??st? obchodn?ho jedn?n?:
- vyhrazuje si odes?latel pr?vo ukon?it kdykoliv jedn?n? o uzav?en? smlouvy, a to z jak?hokoliv d?vodu i bez uveden? d?vodu.
- a obsahuje-li nab?dku, je adres?t opr?vn?n nab?dku bezodkladn? p?ijmout; Odes?latel tohoto e-mailu (nab?dky) vylu?uje p?ijet? nab?dky ze strany p??jemce s dodatkem ?i odchylkou.
- trv? odes?latel na tom, ?e p??slu?n? smlouva je uzav?ena teprve v?slovn?m dosa?en?m shody na v?ech jej?ch n?le?itostech.
- odes?latel tohoto emailu informuje, ?e nen? opr?vn?n uzav?rat za spole?nost ??dn? smlouvy s v?jimkou p??pad?, kdy k tomu byl p?semn? zmocn?n nebo p?semn? pov??en a takov? pov??en? nebo pln? moc byly adres?tovi tohoto emailu p??padn? osob?, kterou adres?t zastupuje, p?edlo?eny nebo jejich existence je adres?tovi ?i osob? j?m zastoupen? zn?m?.

This e-mail and any documents attached to it may be confidential and are intended only for its intended recipients.
If you received this e-mail by mistake, please immediately inform its sender. Delete the contents of this e-mail with all attachments and its copies from your system.
If you are not the intended recipient of this e-mail, you are not authorized to use, disseminate, copy or disclose this e-mail in any manner.
The sender of this e-mail shall not be liable for any possible damage caused by modifications of the e-mail or by delay with transfer of the email.

In case that this e-mail forms part of business dealings:
- the sender reserves the right to end negotiations about entering into a contract in any time, for any reason, and without stating any reasoning.
- if the e-mail contains an offer, the recipient is entitled to immediately accept such offer; The sender of this e-mail (offer) excludes any acceptance of the offer on the part of the recipient containing any amendment or variation.
- the sender insists on that the respective contract is concluded only upon an express mutual agreement on all its aspects.
- the sender of this e-mail informs that he/she is not authorized to enter into any contracts on behalf of the company except for cases in which he/she is expressly authorized to do so in writing, and such authorization or power of attorney is submitted to the recipient or the person represented by the recipient, or the existence of such authorization is known to the recipient of the person represented by the recipient.

	[[alternative HTML version deleted]]



More information about the R-help mailing list