3.9 Pipeline Construction
20210103 Continuing with our pipeline example, we might want a base::summary() of the dataset.
# Summarise subset of variables for observations with rainfall. %>% ds select(min_temp, max_temp, rainfall, sunshine) %>% filter(rainfall >= 1) %>% summary()
## min_temp max_temp rainfall sunshine ## Min. :-8.50 Min. :-4.10 Min. : 1.000 Min. : 0.000 ## 1st Qu.: 8.30 1st Qu.:15.50 1st Qu.: 2.200 1st Qu.: 2.400 ## Median :12.20 Median :19.30 Median : 4.800 Median : 5.500 ## Mean :12.69 Mean :20.15 Mean : 9.675 Mean : 5.366 ## 3rd Qu.:17.10 3rd Qu.:24.40 3rd Qu.: 11.000 3rd Qu.: 8.100 ## Max. :28.90 Max. :46.30 Max. :474.000 Max. :14.200 ## NA's :136 NA's :206 NA's :22639
It could be useful to contrast this with a base::summary() of those observations where there was little or no rain.
# Summarise observations with little or no rainfall. %>% ds select(min_temp, max_temp, rainfall, sunshine) %>% filter(rainfall < 1) %>% summary()
## min_temp max_temp rainfall sunshine ## Min. :-8.70 Min. :-2.10 Min. :0.00000 Min. : 0.00 ## 1st Qu.: 7.20 1st Qu.:19.00 1st Qu.:0.00000 1st Qu.: 6.20 ## Median :11.80 Median :23.80 Median :0.00000 Median : 9.30 ## Mean :11.91 Mean :24.23 Mean :0.05858 Mean : 8.36 ## 3rd Qu.:16.70 3rd Qu.:29.20 3rd Qu.:0.00000 3rd Qu.:11.00 ## Max. :33.90 Max. :48.90 Max. :0.90000 Max. :14.50 ## NA's :620 NA's :701 NA's :78627
Any number of functions can be included in a pipeline to achieve the results we desire. In the following chapters we will see many examples and some will string together ten or more functions. Each step along the way is of itself generally easily understandable. The power is in what we can achieve by stringing together many simple steps to produce something more complex.
Your donation will support ongoing development and give you access to the PDF version of this book. Desktop Survival Guides include Data Science, GNU/Linux, and MLHub. Books available on Amazon include Data Mining with Rattle and Essentials of Data Science. Popular open source software includes rattle, wajig, and mlhub. Hosted by Togaware, a pioneer of free and open source software since 1984.
Copyright © 1995-2021 Graham.Williams@togaware.com Creative Commons Attribution-ShareAlike 4.0.