Hi
The question does not make much sense so as your code. Maybe you shall spend
some time with R tutorials.
1. lapply or sapply is basically hidden cycle
2. function shall return something, yours does not
So if you want some binary outcome from a vector you can use e.g.
f <- function(vector, token) {
response <- vector==token
response
}
So with your colordata
> colordata
id color
1 1 blue
2 2 red
3 3 green
4 4 blue
5 5 orange
You can get this
> colordata$result <- f(colordata$color, "blue")
> colordata
id color result
1 1 blue TRUE
2 2 red FALSE
3 3 green FALSE
4 4 blue TRUE
5 5 orange FALSE
or if you insist on numbers you can transfer it easily.
> colordata$result*1
[1] 1 0 0 1 0
But why do you want to use lapply or sapply is a mystery to me.
Do you have several columns and you want to use same function to those columns?
This is probably the only case I can think of using lapply with such function.
Or you want to change each colour name to some corresponding number? If column
colour is a factor it already consists from unique numbers (as I mentioned in
previous response).
Maybe you shall use dput(yourdata) output together with desired result to help
us better understand your task.
Cheers
Petr
From: Michael Artz [mailto:michaelea...@gmail.com]
Sent: Thursday, April 7, 2016 4:17 PM
To: PIKAL Petr <petr.pi...@precheza.cz>
Subject: Re: [R] simple question on data frames assignment
what about sapply? I guess I am not sure how to iterate with sapply() and a
function like the following
>>The below function does not work, I want to have a function that I can use
>>for sapply() later
f <- function(x) {
response <- ifelse(x[,"Churn"] == "blue", 1, 0)
}
sapply(colordata$color, f(x))
does that question make sense? I just want to have a function that I can pass
to sapply()
On Thu, Apr 7, 2016 at 7:44 AM, PIKAL Petr
<petr.pi...@precheza.cz<mailto:petr.pi...@precheza.cz>> wrote:
Hi
> -----Original Message-----
> From: R-help
> [mailto:r-help-boun...@r-project.org<mailto:r-help-boun...@r-project.org>] On
> Behalf Of Michael
> Artz
> Sent: Thursday, April 7, 2016 1:57 PM
> To: David Barron <dnbar...@gmail.com<mailto:dnbar...@gmail.com>>
> Cc: r-help@r-project.org<mailto:r-help@r-project.org>
> Subject: Re: [R] simple question on data frames assignment
>
> Thaks so much! And how would you incorporate lapply() here?
Why do you want to use lapply? What is a result you want to achieve?
Actually color is factor and it has a numeric value "inside".
> as.numeric(colordata$color)
[1] 1 4 2 1 3
Cheers
Petr
>
> On Thu, Apr 7, 2016 at 6:52 AM, David Barron
> <dnbar...@gmail.com<mailto:dnbar...@gmail.com>> wrote:
>
> > ifelse is vectorised, so just use that without the loop.
> >
> > colordata$response <- ifelse(colordata$color == 'blue', 1, 0)
> >
> > David
> >
> > On 7 April 2016 at 12:41, Michael Artz
> > <michaelea...@gmail.com<mailto:michaelea...@gmail.com>> wrote:
> >
> >> Hi I'm not sure how to ask this, but its a very easy question to
> >> answer for an R person.
> >>
> >> What is an easy way to check for a column value and then assigne a
> >> new column a value based on that old column value?
> >>
> >> For example, Im doing
> >> colordata <- data.frame(id = c(1,2,3,4,5), color = c("blue", "red",
> >> "green", "blue", "orange")) for (i in 1:nrow(colordata)){
> >> colordata$response[i] <- ifelse(colordata[i,"color"] == "blue", 1,
> >> 0) }
> >>
> >> which works, but I don't want to use the for loop I want to "vecotrize"
> >> this. How would this be implemented?
> >>
> >> [[alternative HTML version deleted]]
> >>
> >> ______________________________________________
> >> R-help@r-project.org<mailto:R-help@r-project.org> mailing list -- To
> >> UNSUBSCRIBE and more, see
> >> https://stat.ethz.ch/mailman/listinfo/r-help
> >> PLEASE do read the posting guide
> >> http://www.R-project.org/posting-guide.html
> >> and provide commented, minimal, self-contained, reproducible code.
> >>
> >
> >
>
> [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help@r-project.org<mailto:R-help@r-project.org> mailing list -- To
> UNSUBSCRIBE and more, see
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-
> guide.html
> and provide commented, minimal, self-contained, reproducible code.
________________________________
Tento e-mail a jakékoliv k němu připojené dokumenty jsou důvěrné a jsou určeny
pouze jeho adresátům.
Jestliže jste obdržel(a) tento e-mail omylem, informujte laskavě neprodleně
jeho odesílatele. Obsah tohoto emailu i s přílohami a jeho kopie vymažte ze
svého systému.
Nejste-li zamýšleným adresátem tohoto emailu, nejste oprávněni tento email
jakkoliv užívat, rozšiřovat, kopírovat či zveřejňovat.
Odesílatel e-mailu neodpovídá za eventuální škodu způsobenou modifikacemi či
zpožděním přenosu e-mailu.
V případě, že je tento e-mail součástí obchodního jednání:
- vyhrazuje si odesílatel právo ukončit kdykoliv jednání o uzavření smlouvy, a
to z jakéhokoliv důvodu i bez uvedení důvodu.
- a obsahuje-li nabídku, je adresát oprávněn nabídku bezodkladně přijmout;
Odesílatel tohoto e-mailu (nabídky) vylučuje přijetí nabídky ze strany příjemce
s dodatkem či odchylkou.
- trvá odesílatel na tom, že příslušná smlouva je uzavřena teprve výslovným
dosažením shody na všech jejích náležitostech.
- odesílatel tohoto emailu informuje, že není oprávněn uzavírat za společnost
žádné smlouvy s výjimkou případů, kdy k tomu byl písemně zmocněn nebo písemně
pověřen a takové pověření nebo plná moc byly adresátovi tohoto emailu případně
osobě, kterou adresát zastupuje, předloženy nebo jejich existence je adresátovi
či osobě jím zastoupené známá.
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.
________________________________
Tento e-mail a jakékoliv k němu připojené dokumenty jsou důvěrné a jsou určeny
pouze jeho adresátům.
Jestliže jste obdržel(a) tento e-mail omylem, informujte laskavě neprodleně
jeho odesílatele. Obsah tohoto emailu i s přílohami a jeho kopie vymažte ze
svého systému.
Nejste-li zamýšleným adresátem tohoto emailu, nejste oprávněni tento email
jakkoliv užívat, rozšiřovat, kopírovat či zveřejňovat.
Odesílatel e-mailu neodpovídá za eventuální škodu způsobenou modifikacemi či
zpožděním přenosu e-mailu.
V případě, že je tento e-mail součástí obchodního jednání:
- vyhrazuje si odesílatel právo ukončit kdykoliv jednání o uzavření smlouvy, a
to z jakéhokoliv důvodu i bez uvedení důvodu.
- a obsahuje-li nabídku, je adresát oprávněn nabídku bezodkladně přijmout;
Odesílatel tohoto e-mailu (nabídky) vylučuje přijetí nabídky ze strany příjemce
s dodatkem či odchylkou.
- trvá odesílatel na tom, že příslušná smlouva je uzavřena teprve výslovným
dosažením shody na všech jejích náležitostech.
- odesílatel tohoto emailu informuje, že není oprávněn uzavírat za společnost
žádné smlouvy s výjimkou případů, kdy k tomu byl písemně zmocněn nebo písemně
pověřen a takové pověření nebo plná moc byly adresátovi tohoto emailu případně
osobě, kterou adresát zastupuje, předloženy nebo jejich existence je adresátovi
či osobě jím zastoupené známá.
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]]
______________________________________________
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
