convert 12 time stamp to 24 hour

Readers,

Have since tried to plot converted 24 hour data:

testtimedataset
        V1
1 13:01:41
2 13:02:10
3 13:02:38
4 13:03:05
5 13:03259
testdata<-seq(1:5)
plot(testdata~testtimedataset)
Error in function (formula, data = NULL, subset = NULL, na.action = na.fail,  :
  invalid type (list) for variable 'testtimedataset'

Was expecting to see a graph with ordinate values 1:5 for the time
series values on the abscissa. What is the mistake please?

--
r2151
Hello,

You're trying to plot the df, not the column. Try

plot(testdata ~ testtimedataset$V1)

Hope this helps,

Rui Barradas

Em 11-02-2013 13:30, e-letter escreveu:
Readers,

Have since tried to plot converted 24 hour data:

testtimedataset
         V1
1 13:01:41
2 13:02:10
3 13:02:38
4 13:03:05
5 13:03259

testdata<-seq(1:5)
plot(testdata~testtimedataset)
Error in function (formula, data = NULL, subset = NULL, na.action = na.fail,  :
   invalid type (list) for variable 'testtimedataset'

Was expecting to see a graph with ordinate values 1:5 for the time
series values on the abscissa. What is the mistake please?

--
r2151

______________________________________________
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.

Hi
-----Original Message-----
From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-
project.org] On Behalf Of e-letter
Sent: Monday, February 11, 2013 2:31 PM
To: r-help at r-project.org
Subject: Re: [R] convert 12 time stamp to 24 hour

Readers,

Have since tried to plot converted 24 hour data:

testtimedataset
        V1
1 13:01:41
2 13:02:10
3 13:02:38
4 13:03:05
5 13:03259

testdata<-seq(1:5)
plot(testdata~testtimedataset)
Error in function (formula, data = NULL, subset = NULL, na.action =
na.fail,  :
  invalid type (list) for variable 'testtimedataset'

Was expecting to see a graph with ordinate values 1:5 for the time
series values on the abscissa. What is the mistake please?
The main mistake is that you did not pay attention to provided documentation especially R-intro.

You try to plot a data frame against a vector testdata. We do not know, what is testtimedataset. You shall provide at least 

str(testtimedataset)
or better
dput(testtimedataset)

Anyway, by

plot(testdata~testtimedataset$V1)

you will get rid of error message but depending on testtimedataset mode you can get different one.

Regards
Petr
--
r2151

______________________________________________
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.
str(testtimedataset)
With my real data set, revealed that after conversion, the time series
data consists of 'chr' which I guess means character type data,
reporting the following error:

Error in plot.window(...) : need finite 'xlim' values
In addition: Warning messages:
1: In xy.coords(x, y, xlabel, ylabel, log) : NAs introduced by coercion
2: In min(x) : no non-missing arguments to min; returning Inf
3: In max(x) : no non-missing arguments to max; returning -Inf

Does this mean I must convert the 24-hour time series values to
POSIX*t type objects; if so how please?
Anyway, by

plot(testdata~testtimedataset$V1)

you will get rid of error message but depending on testtimedataset mode you
can get different one.

Confirmed, thanks.
Hi
-----Original Message-----
From: e-letter [mailto:inpost at gmail.com]
Sent: Monday, February 11, 2013 3:11 PM
To: PIKAL Petr
Cc: r-help at r-project.org
Subject: Re: [R] convert 12 time stamp to 24 hour

On 11/02/2013, PIKAL Petr <petr.pikal at precheza.cz> wrote:
str(testtimedataset)
With my real data set, revealed that after conversion, the time series
data consists of 'chr' which I guess means character type data,
Do not guess. There is extensive help in R which you can ivoke by"?".

?mode
?typeof
reporting the following error:

Error in plot.window(...) : need finite 'xlim' values In addition:
Warning messages:
1: In xy.coords(x, y, xlabel, ylabel, log) : NAs introduced by coercion
2: In min(x) : no non-missing arguments to min; returning Inf
3: In max(x) : no non-missing arguments to max; returning -Inf

Does this mean I must convert the 24-hour time series values to POSIX*t
Yes.
type objects; if so how please?
?strptime

Regards
Petr
Anyway, by

plot(testdata~testtimedataset$V1)

you will get rid of error message but depending on testtimedataset
mode you can get different one.

Confirmed, thanks.