d3.scaleQuantize and Domain Boundary Clamping

When mapping quantitative data to discrete range values using d3.scaleQuantize, the behavior of values falling outside the defined domain can vary based on the library version and the explicit configuration of the clamp setting.

In responsive layouts where input data may exceed the initial domain, the default clamping state determines whether out-of-range values are mapped to the nearest range extent or handled as undefined. This becomes a critical design decision when upgrading from d3 v3 to v4 or v5, as the internal reorganization of scale logic may alter how boundaries are treated.

• What is the default clamp state for d3.scaleQuantize in d3 v5 compared to v3?
• How does the output differ when scale.clamp(true) is applied to a value exceeding the domain maximum?