# Read data file
Bridges <- read.csv("https://raw.githubusercontent.com/vskrelja/607_DataAcqMgt_Skrelja/master/Bridges_Data.csv", header=FALSE)
# Read Data Dictionary
Data_Dict <- read.table("https://raw.githubusercontent.com/vskrelja/607_DataAcqMgt_Skrelja/master/Bridges_Data_Dictionary.csv", header=TRUE, sep=",")
# Create a list of column names
column_list <- as.character(Data_Dict$name)
# Assign column names
names(Bridges) <- column_list
head(Bridges)
## IDENTIF RIVER LOCATION ERECTED PURPOSE LENGTH LANES CLEAR-G T-OR-D
## 1 E1 M 3 1818 HIGHWAY ? 2 N THROUGH
## 2 E2 A 25 1819 HIGHWAY 1037 2 N THROUGH
## 3 E3 A 39 1829 AQUEDUCT ? 1 N THROUGH
## 4 E5 A 29 1837 HIGHWAY 1000 2 N THROUGH
## 5 E6 M 23 1838 HIGHWAY ? 2 N THROUGH
## 6 E7 A 27 1840 HIGHWAY 990 2 N THROUGH
## MATERIAL SPAN REL-L TYPE
## 1 WOOD SHORT S WOOD
## 2 WOOD SHORT S WOOD
## 3 WOOD ? S WOOD
## 4 WOOD SHORT S WOOD
## 5 WOOD ? S WOOD
## 6 WOOD MEDIUM S WOOD
# Create dataframe with subset of columns and rows
Bridges_Prewar <- Bridges[Bridges$ERECTED <= 1945, c("ERECTED", "PURPOSE", "TYPE", "MATERIAL")]
summary(Bridges_Prewar)
## ERECTED PURPOSE TYPE MATERIAL
## Min. :1818 AQUEDUCT: 4 SIMPLE-T:42 ? : 0
## 1st Qu.:1882 HIGHWAY :56 WOOD :16 IRON :11
## Median :1898 RR :32 SUSPEN :11 STEEL:66
## Mean :1896 WALK : 1 CANTILEV:10 WOOD :16
## 3rd Qu.:1921 ARCH : 9
## Max. :1945 CONT-T : 4
## (Other) : 1
Bridges_Postwar <- Bridges[Bridges$ERECTED > 1945, c("ERECTED", "PURPOSE", "TYPE", "MATERIAL")]
summary(Bridges_Postwar)
## ERECTED PURPOSE TYPE MATERIAL
## Min. :1950 AQUEDUCT: 0 CONT-T :6 ? : 2
## 1st Qu.:1953 HIGHWAY :15 ARCH :4 IRON : 0
## Median :1959 RR : 0 ? :2 STEEL:13
## Mean :1963 WALK : 0 SIMPLE-T:2 WOOD : 0
## 3rd Qu.:1972 CANTILEV:1
## Max. :1986 NIL :0
## (Other) :0