R Notebook

This is an R Markdown Notebook. When you execute code within the notebook, the results appear beneath the code.

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# download the datasets
dt_training <- read.csv(url(UrlTrain))
dt_testing  <- read.csv(url(UrlTest))
features <- names(dt_testing[,colSums(is.na(dt_testing)) == 0])[8:59]
# Only use features used in testing cases.
dt_training <- dt_training[,c(features,"classe")]
dt_testing <- dt_testing[,c(features,"problem_id")]
dim(dt_training)

[1] 19622    53

dim(dt_testing)

[1] 20 53

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