WaMaSim - Water Management Simulator

WaMaSim is an R package that simulates the effect of different rehabilitation strategies for water distribution systems. It is an education tool used for the Water Infrastructure Experimental and Computer Laboratory at ETH Zurich, Switzerland.

Installation

Install R and R-Studio or any other editor.
Install devtools (type in the R command line)

install.packages("devtools")

Install WaMaSim (type in the R command line)

library(devtools)
install_github("scheidan/WaMaSim")

Usage

This is a minimal example of how you can run the simulation:

 library(WaMaSim)
 
 ## -----------
 ## define model parameters
 
 ## Define the annual probability of a failure
prob.failure.exp <- function(age, age.last.failure, n.failure) {
 if(n.failure==0){
 return(1/30)
 } else {
 return(1/10)
 }
}
 
 ## define a complicated (and probably useless) rehabilitation strategy
mystrategy <- . %>%
 replace.n.highest.risk(n=2, prob.failure=prob.failure.exp) %>%
 replace.more.failures.than(failures=5) %>%
 replace.older.than(age=70, max.cost=2e6) %>%
 replace.n.oldest(n=3) %>%
 replace.n.random(n=2)
 ## This means: every year (if we have enough budget!), replace first the 2 pipes
 ## with the highest risk, then all pipes with more than 5 failures,
 ## then all pipes older then 70 years (up to costs of 2e6), then the 3
 ## oldest pipes remaining, and finally replace 2 randomly selected pipes.
 
 
 ## -----------
 ## run the simulation
 
result <- simulate_network(n.years = 100, # run it for 100 years
 expansion = 10, # build 10 pipes per year (if money is available)
 rehabilitation = mystrategy, # use the strategy defined above
 prob.failure = prob.failure.exp, # use the probability function defined above
 income = 1e6, # the annual income
 initial.budget = 1e7,
 initial.inventory = 50, # start the simulation with 50 new pipes
 free.expansion = FALSE) #
 
 ## look at some results
 str(result)
 str(result$time.100)
 
 
 ## -----------
 ## plots
 
 par(mfrow=c(3,1))
 
 ## budget
 plot(result$time, result$budget, type="l")
 abline(h=0, col=2)
 
 ## pipes built per year
 plot(result$time, pipes.built.per.year(result))
 
 ## annual costs
 plot(result$time, costs.per.year(result, income=1e6))

See the package help for more information.

Package development

The packages devtools, testthat, and roxygen2 are required. To build and test this package use the following workflow:

 library(devtools)
 
package.path = "WaMaSim/" # path must point to the folder containing the WaMaSim files
 
 ## simulate a new package installation
 load_all(package.path)
 
 ## run tests
 test(package.path) # this runs the tests in the `test` folder of the package
 test_coverage(package.path) # needs package 'covr' to be installed
 
 ## build documentation (uses Roxygen2)
 document(package.path)
 
 ## run R CMD checks
 check(package.path, cran=TRUE, manual=TRUE)
 
 ## build package for CRAN submission
 build(pkg=package.path)