Reshape2- dcast problem

jarmy · February 14, 2020, 1:48am

Having a problem running dcast in Reshape2.

AirQLong <- melt(data = airquality,id.vars = c("Month","Day"), variable.name = "climate_variable", value.name = "climate_value",na.rm = TRUE)
AirQLong

acast(AirQLong, Day ~ Month ~ climate_variable)
acast(AirQLong, Month ~ climate_variable, mean)
acast(AirQLong, Month ~ climate_variable, mean, margins = TRUE)

AirQWide <-dcast(AirQLong, month ~ variable, mean, fun.aggregate = c("Month", "climate_variable"))

getting "Error in FUN(X[[i]], ...) : object 'variable' not found" everytime. Can anyone please help solve my dcast formula

nirgrahamuk · February 14, 2020, 2:04am

Do you maybe mean climate_variable rather than variable?

jarmy · February 14, 2020, 2:19am

i have tried both ways and the error still shows up. heres a screenshot on my work

andresrcs · February 14, 2020, 2:46am

Hi!

To help us help you, could you please prepare a reproducible example (reprex) illustrating your issue? Please have a look at this guide, to see how to create one:

FAQ: How to do a minimal reproducible example ( reprex ) for beginners Guides & FAQs

A minimal reproducible example consists of the following items: A minimal dataset, necessary to reproduce the issue The minimal runnable code necessary to reproduce the issue, which can be run on the given dataset, and including the necessary information on the used packages. Let's quickly go over each one of these with examples: Minimal Dataset (Sample Data) You need to provide a data frame that is small enough to be (reasonably) pasted on a post, but big enough to reproduce your issue. Let's say, as an example, that you are working with the iris data frame head(iris) #> Sepal.Length Sepal.Width Petal.Length Petal.Width Species #> 1 5.1 3.5 1.4 0.2…

jarmy · February 14, 2020, 2:53am

Does this help?

andresrcs · February 14, 2020, 2:56am

Not really, that is a screenshot, we can't copy your code and data from there to try to reproduce your issue and give you a solution.
Please follow the link I gave you and try to make a proper reproducible example.

jarmy · February 14, 2020, 3:17am

library(reshape2)

df <- melt(data = airquality,id.vars = c("Month","Day"), variable.name = "climate_variable", value.name = "climate_value",na.rm = TRUE)
head(df)

AirQWide <-dcast(AirQLong, month ~ climate_variable, mean, fun.aggregate = c("Month", "climate_variable"))

jarmy · February 14, 2020, 3:18am

Is that what you are asking for?

andresrcs · February 14, 2020, 3:23am

Please read the guide in the link, you are not providing sample data. If you take the time to read it, you will notice is actually pretty simple to do.

jarmy · February 14, 2020, 3:41am

library(reshape2)

df <- data.frame(stringsAsFactors = FALSE, Month= c(5,5,5,5,5), Day= c(1,2,3,4,6), climate_variable= c("Ozone","Ozone","Ozone","Ozone","Ozone"),climate_value= c(41,36,12,18,28))
df

AirQWide <-dcast(AirQLong, month ~ climate_variable, mean, fun.aggregate = c("Month", "climate_variable"))

andresrcs · February 14, 2020, 4:38am

Is this what you are trying to do?

library(reshape2)

df <- data.frame(stringsAsFactors = FALSE,
                 Month= c(5,5,5,5,5),
                 Day= c(1,2,3,4,6),
                 climate_variable= c("Ozone","Ozone","Ozone","Ozone","Ozone"),
                 climate_value= c(41,36,12,18,28))

dcast(df, Month ~ climate_variable, mean)
#> Using climate_value as value column: use value.var to override.
#>   Month Ozone
#> 1     5    27

^{Created on 2020-02-14 by the reprex package (v0.3.0.9001)}