How to Analyze Price Changes in a DataFrame Using R's Apply Functionality
Here is the code with comments and improvements:
# Find column matches for price # Apply which to compare each row with the corresponding price in the "Price" column change <- apply(DF[, 3:62] == DF[,"Price"], 1, function(x) which(x)) # Update the "change" column for C # Multiply by -1 if the column matches DF$change[DF[,"C"]] <- change[DF[,"C"]] * (-1) # Find column matches for old price in preceding row if M pos2 <- apply(DF[which(DF[,"M"]) - 1, 3:62] == DF[,"Price"], 1, function(x) which(x)) # Update the "change" column for M # Subtract the position of the old price from the current price DF$change[DF[,"M"]] <- pos2[DF[,"M"]] - change[DF[,"M"]] # Print the updated "change" column print(DF$change) Note that I’ve also replaced apply(DF[, 3:62] == DF[,66], 1, which) with function(x) which(x) to make it more concise and readable.
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Automating iOS Screen Capture with Cropped Status Bars =====================================================
As developers, we’re often tasked with creating high-quality screenshots for app submissions to the App Store. However, one common challenge is cropping out the status bar from these screenshots, which can be a tedious and error-prone process. In this article, we’ll explore various techniques for automating this task, including using Python and the Pillow library.
Background The App Store requires that all submitted screenshots have the status bar cropped out.
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The current solution provided uses an Objective-C library called NSLocale-ISO639_2, which offers a more accurate way of getting the three-digit country code in addition to the two-digit code. However, the task of creating this extension for Swift can be accomplished by loading a bundle containing ISO 639-1 to ISO 639-2 mappings.