Review for Quiz 1: Examples: Filter: 08-24-2018

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# Review for Quiz 1: Example 1: 08-24-2018
# dplyr verbs: Filter
# dplyr is a package used for manipulating data
# Filter is used to get a subset of records from a dataset
# Load dplyr and gapminder
# If dplyr and/or gapminder are not installed, you must first install these packages
# gapminder is a database of economic indicators for countries available as a package in R
library (gapminder)
library(dplyr)
# Show the observations for 1997
# Write the dataset name (gapminder) followed by the pipe operators %>%
# Then, use filter to choose records that satisfy a condition
gapminder %>%
  filter(year == 1997)

#Y ou can combine multiple conditions using &
gapminder %>%
  filter(year == 1997 & country == "China")

# Review for Quiz 1: Example 2: 08-24-2018
# Loading data
# If you are using data in a csv file, you must first import it in R Studio
# Import Fee1.csv sent to you 
# Use head(Fee1) to view the first few records of the Fee1 table
head(Fee1)

Fee1 %>%
  filter(GC == 0)

# Review for Quiz 1: Example 3: 08-24-2018 
# You can store the results of filtering in another dataset
#First, view the Fee1 dataset. How many observations are there in this dataset?
Fee1

# Filter and store the results in FeeGC
FeeGC = Fee1 %>%
  filter(GC == 0)
# Data is stored in FeeGC.  Type FeeGC to view the results
FeeGC 

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