d3 create svg element instead of append code example

Example 1: using d3 to add svg box example

<line x1="100" y1="100" x2="500" y2="100" />

Example 2: using d3 to add svg box example

<svg width="500" height="500">
    <line x1="100" y1="50" x2="500" y2="50" stroke="black"/>
</svg>