7.1 Get Overview of Data

A first step is getting an overview of the whole data set and specific series of it.

7.1.1 Load data

Load test data set in a data frame (e.g. from a csv-file):

## Warning: 3 failed to parse.

7.1.2 Names

Show the column headers of a data frame:

names(df)

## [1] "time"               "energyHeatingMeter" "supplyTempHeating"

7.1.3 Structure

Show the structure of the data frame:

str(df)

## 'data.frame':    22317 obs. of  3 variables:
##  $ time              : POSIXct, format: "2018-03-03 00:00:00" "2018-03-03 01:00:00" ...
##  $ energyHeatingMeter: num  45020 NA NA NA NA ...
##  $ supplyTempHeating : num  24.7 24.1 23.7 23.4 31.6 ...

7.1.4 Head/Tail

Show the first and last values:

head(df)

##                  time energyHeatingMeter supplyTempHeating
## 1 2018-03-03 00:00:00           45019.81             24.73
## 2 2018-03-03 01:00:00                 NA             24.06
## 3 2018-03-03 02:00:00                 NA             23.73
## 4 2018-03-03 03:00:00                 NA             23.45
## 5 2018-03-03 04:00:00                 NA             31.59
## 6 2018-03-03 05:00:00                 NA             29.14

tail(df)

##                      time energyHeatingMeter supplyTempHeating
## 22312 2020-09-17 15:00:00                 NA                NA
## 22313 2020-09-17 16:00:00                 NA                NA
## 22314 2020-09-17 17:00:00                 NA                NA
## 22315 2020-09-17 18:00:00                 NA                NA
## 22316 2020-09-17 19:00:00                 NA                NA
## 22317 2020-09-17 20:00:00                 NA                NA

Note: if you want to show only the first three entries, you can type head(df,3)

7.1.5 Five number summary

Reveals details about the distribution of the data:

summary(df$supplyTempHeating)

##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max.    NA's 
##   18.37   23.35   24.61   25.72   27.49   44.68     362