fresh block by walkerjeffd

index.html

<!DOCTYPE html>
<head>
  <meta charset="utf-8">
  <script src="https://d3js.org/d3.v4.min.js"></script>
  <style>
    body { margin:0;position:fixed;top:0;right:0;bottom:0;left:0; }
    
.axis {
  font: 10px sans-serif;
}

.axis path,
.axis line {
  fill: none;
  stroke: #000;
  shape-rendering: crispEdges;
}

.axis--x path {
  display: none;
}

.line {
  fill: none;
  stroke: steelblue;
  stroke-width: 1.5px;
}
  </style>
</head>

<body>
<script>
    
  var margin = {top: 20, right: 20, bottom: 30, left: 50},
      width = 960 - margin.left - margin.right,
      height = 500 - margin.top - margin.bottom;

  function compute(params) {
	  var Zc = params.Zc, // control depth (cm)
        Zw = params.Zw, // weir depth (cm)
        W = params.W,     // mean cell width = area / flow path length (km)
        a = params.a,     // empirical
        b = params.b,     // empirical
      pump_capacity = params.pump_capacity;

  var Z_arr = d3.range(0, 100, 1);

  var Q_arr = Z_arr.map(function (Z) {
    var Q = W * a * Math.pow((Z - Zw), b);
    //   console.log(Z, Q)
      return Z < Zc && Z < Zw ? 0 :
      Q > pump_capacity ? pump_capacity : Q;
    });

    return d3.zip(Z_arr, Q_arr);
  }

  var data = compute({Zc: 40, Zw: 40, W: 1, a: 1, b: 1.5, pump_capacity: 100});

  var x = d3.scaleLinear()
	  .domain([0, 100])
    .range([0]);

  var y = d3.scaleLinear()
    .domain([0, 110])
    .range([height, 0]);

  var line = d3.line()
    .x(function(d) { return x(d[0]); })
    .y(function(d) { return y(d[1]); });

  var svg = d3.select("body").append("svg")
      .attr("width", width + margin.left + margin.right)
      .attr("height", height + margin.top + margin.bottom)
  	.append("g")
    .attr("transform", "translate(" + margin.left + "," + margin.top + ")");


  x.domain(d3.extent(data, function(d) { return d[0]; }));
  y.domain(d3.extent(data, function(d) { return d[1]; }));

  svg.append("g")
      .attr("class", "axis axis--x")
      .attr("transform", "translate(0," + height + ")")
      .call(d3.axisBottom(x));

  svg.append("g")
      .attr("class", "axis axis--y")
      .call(d3.axisLeft(y))
    .append("text")
      .attr("class", "axis-title")
      .attr("transform", "rotate(-90)")
      .attr("y", 6)
      .attr("dy", ".71em")
      .style("text-anchor", "end")
      .text("Q");

  svg.append("path")
      .datum(data)
      .attr("class", "line")
      .attr("d", line);
</script>
</body>