| # Licensed to the Apache Software Foundation (ASF) under one or more |
| # contributor license agreements. See the NOTICE file distributed with |
| # this work for additional information regarding copyright ownership. |
| # The ASF licenses this file to You under the Apache License, Version 2.0 |
| # (the "License"); you may not use this file except in compliance with |
| # the License. You may obtain a copy of the License at |
| # |
| # http://www.apache.org/licenses/LICENSE-2.0 |
| # |
| # Unless required by applicable law or agreed to in writing, software |
| # distributed under the License is distributed on an "AS IS" BASIS, |
| # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| # See the License for the specific language governing permissions and |
| # limitations under the License. |
| # |
| #------------------------------------------------------------------------------ |
| # R source file to validate Poisson distribution tests in |
| # org.apache.commons.math.distribution.PoissonDistributionTest |
| # |
| # To run the test, install R, put this file and testFunctions |
| # into the same directory, launch R from this directory and then enter |
| # source("<name-of-this-file>") |
| # |
| # R functions used |
| # dpois(x, lambda, log = FALSE) <-- density |
| # ppois(q, lambda, lower.tail = TRUE, log.p = FALSE) <-- distribution |
| # pnorm(q, mean=0, sd=1, lower.tail = TRUE, log.p = FALSE) <-- normal dist. |
| #------------------------------------------------------------------------------ |
| tol <- 1E-10 |
| #------------------------------------------------------------------------------ |
| # Function definitions |
| |
| source("testFunctions") # utility test functions |
| |
| # function to verify density computations |
| |
| verifyDensity <- function(points, expected, lambda, tol) { |
| rDensityValues <- rep(0, length(points)) |
| i <- 0 |
| for (point in points) { |
| i <- i + 1 |
| rDensityValues[i] <- dpois(point, lambda, log = FALSE) |
| } |
| output <- c("Density test lambda = ", lambda) |
| if (assertEquals(expected, rDensityValues, tol, "Density Values")) { |
| displayPadded(output, SUCCEEDED, WIDTH) |
| } else { |
| displayPadded(output, FAILED, WIDTH) |
| } |
| } |
| |
| # function to verify distribution computations |
| |
| verifyDistribution <- function(points, expected, lambda, tol) { |
| rDistValues <- rep(0, length(points)) |
| i <- 0 |
| for (point in points) { |
| i <- i + 1 |
| rDistValues[i] <- ppois(point, lambda, log = FALSE) |
| } |
| output <- c("Distribution test lambda = ", lambda) |
| if (assertEquals(expected, rDistValues, tol, "Distribution Values")) { |
| displayPadded(output, SUCCEEDED, WIDTH) |
| } else { |
| displayPadded(output, FAILED, WIDTH) |
| } |
| } |
| |
| # function to verify normal approximation |
| |
| verifyNormalApproximation <- function(expected, lambda, lower, upper, tol) { |
| rValue <- pnorm(upper, mean=lambda, sd=sqrt(lambda), lower.tail = TRUE, |
| log.p = FALSE) - |
| pnorm(lower, mean=lambda, sd=sqrt(lambda), lower.tail = TRUE, |
| log.p = FALSE) |
| output <- c("Normal approx. test lambda = ", lambda, " upper = ", |
| upper, " lower = ", lower) |
| if (assertEquals(expected, rValue, tol, "Distribution Values")) { |
| displayPadded(output, SUCCEEDED, WIDTH) |
| } else { |
| displayPadded(output, FAILED, WIDTH) |
| } |
| } |
| |
| cat("Poisson distribution test cases\n") |
| |
| # stock tests |
| |
| lambda <- 4.0 |
| densityPoints <- c(-1,0,1,2,3,4,5,10,20) |
| densityValues <- c(0, 0.0183156388887, 0.073262555555, 0.14652511111, |
| 0.195366814813, 0.195366814813, 0.156293451851, |
| 0.00529247667642, 8.27746364655e-09) |
| verifyDensity(densityPoints, densityValues, lambda, tol) |
| |
| |
| distributionPoints <- c(-1, 0, 1, 2, 3, 4, 5, 10, 20) |
| distributionValues <- c(0, 0.0183156388887, 0.0915781944437, 0.238103305554, |
| 0.433470120367, 0.62883693518, 0.78513038703, |
| 0.99716023388, 0.999999998077) |
| verifyDistribution(distributionPoints, distributionValues, lambda, tol) |
| |
| # normal approximation tests |
| |
| lambda <- 100 |
| verifyNormalApproximation(0.706281887248, lambda, 89.5, 110.5, tol) |
| |
| lambda <- 10000 |
| verifyNormalApproximation(0.820070051552, lambda, 9899.5, 10200.5, tol) |
| |
| displayDashes(WIDTH) |
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