Apple introduced SwiftUI Charts at WWWDC 2022, which makes it incredibly easy to create charts within SwiftUI views. Charts are a great way of presenting visual data in a rich format that is easy to understand. This article shows how to easily create a line chart with so much less code than was previously used to …
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Data stored in a csv file can often contain JSON objects in one of the fields. The csv data can easily be loaded into a Pandas Dataframe for analysis. Fields of interest in the JSON object can also be extracted into their own column easily using Dataframe.Apply.
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Reduce is a simple way to perform an operation over each element in a collection and condense down to a single value. It is commonly used on a list of numeric values to add up all the values.
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SwiftUI does not have a control to present an open/save dialog to the user to allow saving files to the macOS filesystem. One could build such a view from scratch, but it is easier to use NSSavePanel from AppKit. This article demonstrates how to use NSSavePanel to get the URL for the file to be saved and use …
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Swift provides a number of map methods to transform elements in Swift collections and return the transformed data in a new Array. The transform is supplied in a trailing closure to the map function. This article looks at Map, FlatMap and CompactMap on collections in Swift as well as MapValues in Dictionary.
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A dictionary stores a list of key/value pairs in an unordered structure that is fast and efficient at adding elements and finding elements by a key. Each element in the dictionary is identified using its key, which is a hashable type such as a string or number.
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TabularData was introduced in iOS 15 and can be used to load data from csv or json format into a DataFrame to explore and manipulate. This is not Python Pandas, but it does provide some basic functionality for exploring data and is fast and efficient. In this article, the data on the deaths from Covid is loaded, …
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Dependency Injection is a technique to pass in one or more dependent object to another object. This article will build on the Weather App to pass in the weather service to the weather ViewModel at initialisation. This will allow the use of a mock weather service to test the ViewModel in unit tests without requiring any …
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Code style can be a controversial topic and lead to some passionate debates between developers. The use of a tool to enforce a set of rules on style can be very helpful to avoid contentious arguments and ensure the code is consistent throughout a project. SwiftLint can easily be incorporated into Xcode projects to flag …
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Last week, we retrieved weather data from Open Weather API to demonstrate how to parse JSON data. The weather data is retrieved asynchronously, which may result in a delay before the UI is updated. This article shows how to display a progress view while the data is being fetched, to provide feedback that something is …
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