How to conditionally remove elements with d3?

@cortez.connelly 

To conditionally remove elements with D3, you can use the selection.filter() method. This method allows you to filter the selection based on a specified condition and remove the elements that don't meet the condition.

Here is an example:

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// Select all <circle> elements in the SVG
const circles = d3.select("svg").selectAll("circle");

// Filter the selection based on a condition (e.g., remove circles with radius greater than 10)
circles.filter(function(d, i) {
    return d.radius > 10;
}).remove();

In this example, the filter() method takes a callback function that is called for each element in the selection. The callback function has two arguments: d (data bound to the element) and i (index of the element in the selection). Inside the callback function, you can specify the condition that you want to use for filtering. In this case, it checks if the radius property of the data is greater than 10.

If the condition is true for an element, it is kept in the selection. If the condition is false, the element is removed from the selection. Finally, you can call the remove() method to delete the selected elements from the DOM.

Note that the filter() method returns a new selection, so you can continue chaining other methods to manipulate the filtered selection further if needed.