From f5c70f6f0133f4d77c6782841e807c679f8504e7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Felix=20Ramnel=C3=B6v?= <felra653@student.liu.se>
Date: Tue, 10 Dec 2024 15:56:03 +0100
Subject: [PATCH] Lab 3: Code cleanup for assignment 2
---
lab3/assignment2.R | 100 +++++++++++++++++++++++++++++----------------
1 file changed, 65 insertions(+), 35 deletions(-)
diff --git a/lab3/assignment2.R b/lab3/assignment2.R
index d75dcc0..b0e655d 100644
--- a/lab3/assignment2.R
+++ b/lab3/assignment2.R
@@ -13,7 +13,7 @@ h_time <- 4
a <- 58.4274
b <- 14.826
-date <- "1960-07-11"
+date <- "1966-12-10"
times <- c(
"04:00:00",
"06:00:00",
@@ -32,25 +32,36 @@ times <- c(
st <- st[st$date <= date, ] # Filter out posterior dates
st$time <- strptime(st$time, format = "%H:%M:%S")
-dist = seq(0, 300000)
-plot(exp(-abs(dist) ^ 2 / (2 * h_distance ^ 2)),
- type = 'l',
- xlab = "Physical distance",
- ylab = "Kernel")
+gaussian_kernel <- function(x, h) {
+ exp(-(x ^ 2) / (2 * h ^ 2))
+}
+
+dist = seq(0, 300000, length.out = 1000)
+plot(
+ gaussian_kernel(dist, h_distance),
+ type = 'l',
+ xlab = "Physical distance",
+ ylab = "Kernel value",
+ main = "Gaussian distance kernel"
+)
-#choosing appropriate smoothing coefficient for days
-dist = seq(0, 100)
-plot(exp(-abs(dist) ^ 2 / (2 * h_date ^ 2)),
- type = 'l',
- xlab = "Distance in days",
- ylab = "Kernel")
+dist = seq(0, 60)
+plot(
+ gaussian_kernel(dist, h_date),
+ type = 'l',
+ xlab = "Distance in days",
+ ylab = "Kernel value",
+ main = "Gaussian date kernel"
+)
-#choosing appropriate smoothing coefficient for hours
dist = seq(0, 18)
-plot(exp(-abs(dist) ^ 2 / (2 * h_time ^ 2)),
- type = 'l',
- xlab = "Distance in hours",
- ylab = "Kernel")
+plot(
+ gaussian_kernel(dist, h_time),
+ type = 'l',
+ xlab = "Distance in hours",
+ ylab = "Kernel value",
+ main = "Gaussian time kernel"
+)
temp_add <- c()
temp_mult <- c()
@@ -59,6 +70,7 @@ for (time in times) {
time <- strptime(time, format = "%H:%M:%S")
+ # Filter out posterior time
st_temp <- st[st$date < date |
(st$date == date &
st$time <= time), ]
@@ -66,26 +78,20 @@ for (time in times) {
distance_kernels <- mapply(function(lat, lon) {
dist <- distHaversine(c(a, b), c(lat, lon))
- exp(-abs(dist) ^ 2 / (2 * h_distance ^ 2))
- }, st_temp$latitude, st$longitude)
-
+ gaussian_kernel(dist, h_distance)
+ }, st_temp$latitude, st_temp$longitude)
- date_kernels <- st_temp$date
- date_kernels <- sapply(date_kernels, function(x_i) {
+ date_kernels <- mapply(function(x_i) {
dist <- as.numeric(as.Date(date) - as.Date(x_i))
- exp(-abs(dist) ^ 2 / (2 * h_date ^ 2))
- })
+ gaussian_kernel(dist, h_date)
+ }, st_temp$date)
- time_kernels <- st_temp$time
- time_kernels <- sapply(time_kernels, function(x_i) {
+ time_kernels <- mapply(function(x_i) {
dist <- as.numeric(difftime(time, x_i, units = "hours"))
- exp(-abs(dist) ^ 2 / (2 * h_time ^ 2))
- })
-
-
-
+ gaussian_kernel(dist, h_time)
+ }, st_temp$time)
kernels_add <- distance_kernels + date_kernels + time_kernels
@@ -94,10 +100,34 @@ for (time in times) {
temp_add <<- c(temp_add,
sum(kernels_add * st_temp$air_temperature) / sum(kernels_add))
temp_mult <<- c(temp_mult,
- sum(kernels_mult * st_temp$air_temperature) / sum(kernels_mult))
-
+ sum(kernels_mult * st_temp$air_temperature) / sum(kernels_mult))
}
-plot(temp_add, type = "o")
-plot(temp_mult, type = "o")
\ No newline at end of file
+plot(
+ temp_add,
+ type = "o",
+ xaxt = "n",
+ xlab = "Time",
+ ylab = "Temperature",
+ main = "Added kernels"
+)
+axis(
+ 1,
+ at = 1:length(times),
+ labels = times
+)
+
+plot(
+ temp_mult,
+ type = "o",
+ xaxt = "n",
+ xlab = "Time",
+ ylab = "Temperature",
+ main = "Multiplied kernels"
+)
+axis(
+ 1,
+ at = 1:length(times),
+ labels = times
+)
\ No newline at end of file
--
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