I can solve this problem. Here is the final code: library(dplyr) df %>% mutate(DateTime = as.POSIXct(DateTime, format = "%d/%m/%Y %H:%M"), Date = as.Date(DateTime)) %>% arrange(DateTime) %>% mutate(class = c("increase", "decrease")[(Area - lag(Area) < 0) + 1]) %>% group_by(Date) %>% mutate(prev_max = max(Area), class = case_when( class == "increase" & Area > prev_max ~ "growth", TRUE ~ class)) %>% select(-prev_max) This code first converts DateTime to POSIXct value and Date to Date.

Working with Excel Sheets using Pandas: A Step-by-Step Guide Introduction Pandas is a powerful Python library used for data manipulation and analysis. One of its most popular features is the ability to read and write Excel sheets (.xls, .xlsx, etc.) in various formats. In this article, we will explore how to use pandas to change the column name of an Excel sheet. Prerequisites Before diving into the tutorial, ensure you have the following installed:

Generalized Linear Mixed Models with lme4: A Deep Dive Introduction Generalized linear mixed models (GLMMs) are a popular statistical framework for analyzing data that contain both fixed and random effects. In this article, we will delve into the world of GLMMs using the R package lme4, which provides an efficient and flexible way to fit GLMMs. We will explore the basics of GLMMs, discuss common pitfalls and how to troubleshoot them, and provide a worked example to illustrate key concepts.

Pandas nunique() for Categorical Columns Only, Null Otherwise? In this article, we’ll explore how to use the nunique() function in pandas to count the number of unique values in categorical columns while excluding numerical columns. We’ll also discuss alternative methods and best practices for working with missing data. Introduction The nunique() function is a powerful tool in pandas that allows us to quickly identify the number of unique values in each column of our DataFrame.

Understanding UI Performance on Background Threads in iOS In this article, we will delve into the intricacies of building user interfaces (UI) from background threads in iOS. We’ll explore why calling performSelectorOnMainThread from a background thread may not work as expected and provide practical solutions to overcome these challenges. Introduction to Background Threads and Main Thread In iOS development, there are two primary threads: the main thread and the background thread.

Filling a 5x5 Matrix with -1, 0, and 1 using a For Loop in R As data analysts and scientists often perform repetitive tasks, we need to revisit familiar concepts and explore alternative approaches. In this article, we’ll delve into the world of loops in R and demonstrate how to fill a 5x5 matrix with -1, 0, and 1 using a for loop. Introduction to Loops in R R’s programming language is known for its simplicity and flexibility.

Introduction Loading a Microsoft OneNote (.one) file directly in a UIWebView or converting it to a PDF format programmatically can be a challenging task, especially for those new to iOS development and web technologies like WebView. In this article, we will explore the steps involved in loading an MS OneNote file in a UIWebView and provide examples of how to achieve this using the UIDocumentInteractionController. We’ll also discuss the limitations and potential workarounds when dealing with OneNote files in a WebView.

Understanding the Issue: Cannot Dismiss a View Controller after Dismissing a Media Player View Controller In this article, we will delve into the world of iOS view controllers and explore why it is not possible to dismiss a view controller that presents a media player view controller. Background In iOS development, presenting a view controller is a way to show its content on screen. When a view controller is presented, it becomes the topmost view in the navigation hierarchy.

Understanding Device Orientation in Cocos2d-x As a developer working with Cocos2d-x, you may have encountered situations where you need to adjust the orientation of your game or application based on external factors like screen rotation. In this article, we’ll explore how to flip everything on screen after a fixed interval has elapsed using Cocos2d-x. Introduction Cocos2d-x is a popular open-source framework for building 2D games and interactive applications. It provides a powerful and flexible way to create engaging experiences with its extensive set of features and tools.

Merging Dataframes with Multiple Key Columns Merging dataframes can be a complex task, especially when dealing with multiple key columns. In this article, we will explore how to merge two dataframes, df1 and df2, where df1 has multiple key columns [“A”, “B”, “C”] and df2 has a single key column “ID”. Introduction The problem statement involves merging two dataframes, df1 and df2, with different number of key columns. The goal is to produce an output dataframe that contains all the rows from both input dataframes.