Dear all,
I have a question and need your help please.
I have the following code which is asking user to enter the name of their file.
define<- function()
{
readline("enter the name of your file: ")
}
df=read.table(define(),fill=T,sep="\t",colClasses =
"character")
Now I want if user will input wrong name of file the code should not end and it
should show a message-
if()
{
print("wrong name of the file Please enter again ")
}
now I want to ask what should be the condition of if so that if user will input
wrong file name it will show this message and then i want to use something like
goto so that it should again start with the code which is before if condition-
df=read.table(define(),fill=T,sep="\t",colClasses =
"character")
so the code should be-
define<- function(x)
{
readline("enter the name of your file: ")
}
df=read.table(define(),fill=T,sep="\t",colClasses =
"character") ##starline
if(## some condition here)
{
print("wrong name of the file Please enter again ")
## some goto function so that it should goto (starline)
}
Thanking you,
Warm Regards
Vikas Bansal
Msc Bioinformatics
Kings College London
These are elementary programming constructs. I would suggest you take a look at an online basic (as in elementary, not the Basic language) programming tutorial to see how to do this sort of thing. R does it like many other languages (with ?for, ?while, ?if, etc.). -- Bert On Sun, Jul 24, 2011 at 7:05 AM, Bansal, Vikas <vikas.bansal at kcl.ac.uk> wrote:> Dear all, > > I have a question and need your help please. > I have the following code which is asking user to enter the name of their file. > > define<- function() > ?{ > ?readline("enter the name of your file: ") > ?} > > df=read.table(define(),fill=T,sep="\t",colClasses = "character") > > Now I want if user will input wrong name of file the code should not end and it should show a message- > > if() > { > ?print("wrong name of the file Please enter again ") > > ?} > > now I want to ask what should be the condition of if so that if user will input wrong file name it will show this message and then i want to use something like goto so that it should again start with the code which is before if condition- > > df=read.table(define(),fill=T,sep="\t",colClasses = "character") > > > > > so the code should be- > > define<- function(x) > ?{ > ?readline("enter the name of your file: ") > ?} > > df=read.table(define(),fill=T,sep="\t",colClasses = "character") ? ? ? ? ? ##starline > > > if(## some condition here) > { > ?print("wrong name of the file Please enter again ") > ## some goto function so that it should goto (starline) > ?} > > > > > > > > Thanking you, > Warm Regards > Vikas Bansal > Msc Bioinformatics > Kings College London > ______________________________________________ > R-help at r-project.org mailing list > 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. >-- "Men by nature long to get on to the ultimate truths, and will often be impatient with elementary studies or fight shy of them. If it were possible to reach the ultimate truths without the elementary studies usually prefixed to them, these would not be preparatory studies but superfluous diversions." -- Maimonides (1135-1204) Bert Gunter Genentech Nonclinical Biostatistics
Thanks for you reply.I have seen it and I got that we can use this goto function
in the form of double loop.
like-
for(j in 1:10)
{
df=read.table(define(),fill=T,sep="\t",colClasses =
"character")
if()
{
print("wrong name of the file Please enter again ")}
else{
break()
}
}
but i did not find what should i condition should i give in if statement because
when the user will type the wrong name of the file,my code does not execute and
just showing the eroor
could not find such file
Can you please tell me what condition i should write so that my code should not
stop even if user writes wrong name of input file?
Thanking you,
Warm Regards
Vikas Bansal
Msc Bioinformatics
Kings College London
________________________________________
From: Bert Gunter [gunter.berton at gene.com]
Sent: Sunday, July 24, 2011 3:58 PM
To: Bansal, Vikas
Cc: r-help at r-project.org
Subject: Re: [R] wrong name of input file and goto like function
These are elementary programming constructs. I would suggest you take
a look at an online basic (as in elementary, not the Basic language)
programming tutorial to see how to do this sort of thing. R does it
like many other languages (with ?for, ?while, ?if, etc.).
-- Bert
On Sun, Jul 24, 2011 at 7:05 AM, Bansal, Vikas <vikas.bansal at kcl.ac.uk>
wrote:> Dear all,
>
> I have a question and need your help please.
> I have the following code which is asking user to enter the name of their
file.
>
> define<- function()
> {
> readline("enter the name of your file: ")
> }
>
> df=read.table(define(),fill=T,sep="\t",colClasses =
"character")
>
> Now I want if user will input wrong name of file the code should not end
and it should show a message-
>
> if()
> {
> print("wrong name of the file Please enter again ")
>
> }
>
> now I want to ask what should be the condition of if so that if user will
input wrong file name it will show this message and then i want to use something
like goto so that it should again start with the code which is before if
condition-
>
> df=read.table(define(),fill=T,sep="\t",colClasses =
"character")
>
>
>
>
> so the code should be-
>
> define<- function(x)
> {
> readline("enter the name of your file: ")
> }
>
> df=read.table(define(),fill=T,sep="\t",colClasses =
"character") ##starline
>
>
> if(## some condition here)
> {
> print("wrong name of the file Please enter again ")
> ## some goto function so that it should goto (starline)
> }
>
>
>
>
>
>
>
> Thanking you,
> Warm Regards
> Vikas Bansal
> Msc Bioinformatics
> Kings College London
> ______________________________________________
> R-help at r-project.org mailing list
> 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.
>
--
"Men by nature long to get on to the ultimate truths, and will often
be impatient with elementary studies or fight shy of them. If it were
possible to reach the ultimate truths without the elementary studies
usually prefixed to them, these would not be preparatory studies but
superfluous diversions."
-- Maimonides (1135-1204)
Bert Gunter
Genentech Nonclinical Biostatistics
Please do read at least some basic R documentation before posting here!
In addition, please read the help pages:
help("file.exists")
help("stop") vs. help("print")
help("break") which is not a function
On 24.07.2011 17:35, Bansal, Vikas wrote:> Thanks for you reply.I have seen it and I got that we can use this goto
function in the form of double loop.
>
> like-
>
> for(j in 1:10)
> {
> df=read.table(define(),fill=T,sep="\t",colClasses =
"character")
> if()
> {
> print("wrong name of the file Please enter again ")}
> else{
> break()
> }
> }
>
> but i did not find what should i condition should i give in if statement
because when the user will type the wrong name of the file,my code does not
execute and just showing the eroor
>
> could not find such file
>
> Can you please tell me what condition i should write so that my code should
not stop even if user writes wrong name of input file?
>
> Thanking you,
> Warm Regards
> Vikas Bansal
> Msc Bioinformatics
> Kings College London
> ________________________________________
> From: Bert Gunter [gunter.berton at gene.com]
> Sent: Sunday, July 24, 2011 3:58 PM
> To: Bansal, Vikas
> Cc: r-help at r-project.org
> Subject: Re: [R] wrong name of input file and goto like function
>
> These are elementary programming constructs. I would suggest you take
> a look at an online basic (as in elementary, not the Basic language)
> programming tutorial to see how to do this sort of thing. R does it
> like many other languages (with ?for, ?while, ?if, etc.).
>
> -- Bert
>
> On Sun, Jul 24, 2011 at 7:05 AM, Bansal, Vikas<vikas.bansal at
kcl.ac.uk> wrote:
>> Dear all,
>>
>> I have a question and need your help please.
>> I have the following code which is asking user to enter the name of
their file.
>>
>> define<- function()
>> {
>> readline("enter the name of your file: ")
>> }
>>
>> df=read.table(define(),fill=T,sep="\t",colClasses =
"character")
>>
>> Now I want if user will input wrong name of file the code should not
end and it should show a message-
>>
>> if()
>> {
>> print("wrong name of the file Please enter again ")
>>
>> }
>>
>> now I want to ask what should be the condition of if so that if user
will input wrong file name it will show this message and then i want to use
something like goto so that it should again start with the code which is before
if condition-
>>
>> df=read.table(define(),fill=T,sep="\t",colClasses =
"character")
>>
>>
>>
>>
>> so the code should be-
>>
>> define<- function(x)
>> {
>> readline("enter the name of your file: ")
>> }
>>
>> df=read.table(define(),fill=T,sep="\t",colClasses =
"character") ##starline
>>
>>
>> if(## some condition here)
>> {
>> print("wrong name of the file Please enter again ")
>> ## some goto function so that it should goto (starline)
>> }
>>
>>
>>
>>
>>
>>
>>
>> Thanking you,
>> Warm Regards
>> Vikas Bansal
>> Msc Bioinformatics
>> Kings College London
>> ______________________________________________
>> R-help at r-project.org mailing list
>> 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.
>>
>
>
>
> --
> "Men by nature long to get on to the ultimate truths, and will often
> be impatient with elementary studies or fight shy of them. If it were
> possible to reach the ultimate truths without the elementary studies
> usually prefixed to them, these would not be preparatory studies but
> superfluous diversions."
>
> -- Maimonides (1135-1204)
>
> Bert Gunter
> Genentech Nonclinical Biostatistics
>
> ______________________________________________
> R-help at r-project.org mailing list
> 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.
While you study the documentation as others suggested, may I suggest that you
take a look at the
file.exists()
function. Here is an example of using file.exists().
tmpfile <- define()
if (file.exists(tmpfile)) {
## read the file
} else {
## tell the user to try again
}
On Jul 24, 2011, at 7:05 AM, Bansal, Vikas wrote:
> Dear all,
>
> I have a question and need your help please.
> I have the following code which is asking user to enter the name of their
file.
>
> define<- function()
> {
> readline("enter the name of your file: ")
> }
>
> df=read.table(define(),fill=T,sep="\t",colClasses =
"character")
>
> Now I want if user will input wrong name of file the code should not end
and it should show a message-
>
> if()
> {
> print("wrong name of the file Please enter again ")
>
> }
>
> now I want to ask what should be the condition of if so that if user will
input wrong file name it will show this message and then i want to use something
like goto so that it should again start with the code which is before if
condition-
>
> df=read.table(define(),fill=T,sep="\t",colClasses =
"character")
>
>
>
>
> so the code should be-
>
> define<- function(x)
> {
> readline("enter the name of your file: ")
> }
>
> df=read.table(define(),fill=T,sep="\t",colClasses =
"character") ##starline
>
>
> if(## some condition here)
> {
> print("wrong name of the file Please enter again ")
> ## some goto function so that it should goto (starline)
> }
>
>
>
>
>
>
>
> Thanking you,
> Warm Regards
> Vikas Bansal
> Msc Bioinformatics
> Kings College London
> ______________________________________________
> R-help at r-project.org mailing list
> 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.
--------------------------------------------------------
Don MacQueen
Lawrence Livermore National Laboratory
(925) 423-1062
macqueen1 at llnl.gov