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JVScrollforme

forked from 35degrees's block: JVScrollexample1

<!DOCTYPE html>
<html>
<head>
  <title>Scrolling Sections</title>
  <link rel="stylesheet" type="text/css" href="css/bootstrap.min.css"/>
  <link rel="stylesheet" type="text/css" href="css/style.css"/>
  <script src="https://d3js.org/d3.v4.min.js"></script>
</head>
<body>
<div class="container">
  <div id='graphic'>
    <div id='sections'>
      <section class="step">
        <div class="title">OpenVis Conf 2013</div>
        I did what no presenter should ever do: I watched my own talk.<br/><br/>My first visit to OpenVis Conf in 2013.
      </section>
      <section class="step">
        <div class="title">Filler Words</div>
        As expected, I could only focus on the flaws: the rushed speech, the odd phrases, and, most especially, all the filler words. In fact, I found 180 filler words in my 30 minute talk.
      </section>
      <section class="step">
        <div class="title">My Talk</div>
        Here are all 5,040 words of my talk.
      </section>
      <section class="step">
        <div class="title">My Stumbles</div>
        And here are all the fillers I used in those 30 minutes.
      </section>
      <section class="step">
        <div class="title">Um's, Ah's &amp; Uh's</div>
        I almost exclusively used these three fillers. Um's and Ah's made up over 80%, with Uh's trailing behind.
      </section>
      <section class="step">
        <div class="title">Fillers Over Time</div>
        I hoped that all these blunders were toward the beginning of my talk. And the data suggests that fewer fillers are used as I get into it. Perhaps the talk started out rough and improved as I found my groove.
      </section>
      <section class="step">
        <div class="title">Ramping Back Up</div>
        Unfortunately, the trend does not continue. Midway into the talk my Um's and Ah's spike. I continue to use them pretty consistently throughout the rest of the talk.
      </section>
      <section class="step">
        <div class="title">The Cough Effect</div>
        My theory is that at this critical halfway point in my talk, I heard a dry cough indicative of the audience's waning interest. This caused self-confidence to collapse and forced me out of my groove.<br/><br/>A competing theory is that I just hadn't practiced the last half of my speech as much.
      </section>
      <section class="step">
        <div class="title">Best of Luck to Me in 2015</div>
        The world may never know, or care, but hopefully these insights improve my speaking in 2015. Though preliminary results aren't looking so good.
      </section>
    </div>
    <div id='vis'>
    </div>
    <div id="extra-space">
    </div>
  </div>
</div>
<style>
  
.container {
  width: 890px;
}

#graphic {
  padding-top: 60px;
}

#sections {
  position: relative;
  display: inline-block;
  width: 250px;
  top: 0px;
  z-index: 90;
  padding-bottom: 200px;
}

.step {
  margin-bottom: 200px;
  font-family: "TiemposTextWeb-Regular","Georgia";
  font-size: 16px;
  line-height: 23px;
  color: #767678;
}

#sections .title {
  font-family: Arial,Helvetica,"san-serif";
  font-size: 16px;
  font-weight: bold;
  margin-bottom: 2px;
  color: #262626;
  line-height: 1.2em;
}

#extra-space {
  height: 300px;
}

#vis {
  display: inline-block;
  position: fixed;
  top: 60px;
  z-index: 1;
  margin-left: 0;
  /* height: 600px; */
  /* width: 600px; */
  /* background-color: #ddd; */
}

#vis .title {
  font-size:120px;
  text-anchor: middle;
}

#vis .sub-title {
  font-size:80px;
  text-anchor: middle;
}

.axis path,
.axis line {
  fill: none;
  stroke: #666;
  shape-rendering: crispEdges;
}

.highlight {
  fill: #008080;
  font-weight: bold;
}

.cough-arrow {
  stroke: #000;
  stroke-width: 4px;

}

</style>
  
<script>
/**
 * scroller - handles the details
 * of figuring out which section
 * the user is currently scrolled
 * to.
 *
 */
function scroller() {
  var container = d3.select('body');
  // event dispatcher
  var dispatch = d3.dispatch('active', 'progress');

// d3 selection of all the
  // text sections that will
  // be scrolled through
  var sections = null;

// array that will hold the
  // y coordinate of each section
  // that is scrolled through
  var sectionPositions = [];
  var currentIndex = -1;
  // y coordinate of
  var containerStart = 0;

/**
   * scroll - constructor function.
   * Sets up scroller to monitor
   * scrolling of els selection.
   *
   * @param els - d3 selection of
   *  elements that will be scrolled
   *  through by user.
   */
  function scroll(els) {
    sections = els;

// when window is scrolled call
    // position. When it is resized
    // call resize.
    d3.select(window)
      .on('scroll.scroller', position)
      .on('resize.scroller', resize);

// manually call resize
    // initially to setup
    // scroller.
    resize();

// hack to get position
    // to be called once for
    // the scroll position on
    // load.
    // @v4 timer no longer stops if you
    // return true at the end of the callback
    // function - so here we stop it explicitly.
    var timer = d3.timer(function () {
      position();
      timer.stop();
    });
  }

/**
   * resize - called initially and
   * also when page is resized.
   * Resets the sectionPositions
   *
   */
  function resize() {
    // sectionPositions will be each sections
    // starting position relative to the top
    // of the first section.
    sectionPositions = [];
    var startPos;
    sections.each(function (d, i) {
      var top = this.getBoundingClientRect().top;
      if (i === 0) {
        startPos = top;
      }
      sectionPositions.push(top - startPos);
    });
    containerStart = container.node().getBoundingClientRect().top + window.pageYOffset;
  }

/**
   * position - get current users position.
   * if user has scrolled to new section,
   * dispatch active event with new section
   * index.
   *
   */
  function position() {
    var pos = window.pageYOffset - 10 - containerStart;
    var sectionIndex = d3.bisect(sectionPositions, pos);
    sectionIndex = Math.min(sections.size() - 1, sectionIndex);

if (currentIndex !== sectionIndex) {
      // @v4 you now `.call` the dispatch callback
      dispatch.call('active', this, sectionIndex);
      currentIndex = sectionIndex;
    }

var prevIndex = Math.max(sectionIndex - 1, 0);
    var prevTop = sectionPositions[prevIndex];
    var progress = (pos - prevTop) / (sectionPositions[sectionIndex] - prevTop);
    // @v4 you now `.call` the dispatch callback
    dispatch.call('progress', this, currentIndex, progress);
  }

/**
   * container - get/set the parent element
   * of the sections. Useful for if the
   * scrolling doesn't start at the very top
   * of the page.
   *
   * @param value - the new container value
   */
  scroll.container = function (value) {
    if (arguments.length === 0) {
      return container;
    }
    container = value;
    return scroll;
  };

// @v4 There is now no d3.rebind, so this implements
  // a .on method to pass in a callback to the dispatcher.
  scroll.on = function (action, callback) {
    dispatch.on(action, callback);
  };

return scroll;
}

/**
 * scrollVis - encapsulates
 * all the code for the visualization
 * using reusable charts pattern:
 * https://bost.ocks.org/mike/chart/
 */
var scrollVis = function () {
  // constants to define the size
  // and margins of the vis area.
  var width = 600;
  var height = 520;
  var margin = { top: 0, left: 20, bottom: 40, right: 10 };

// Keep track of which visualization
  // we are on and which was the last
  // index activated. When user scrolls
  // quickly, we want to call all the
  // activate functions that they pass.
  var lastIndex = -1;
  var activeIndex = 0;

// Sizing for the grid visualization
  var squareSize = 6;
  var squarePad = 2;
  var numPerRow = width / (squareSize + squarePad);

// main svg used for visualization
  var svg = null;

// d3 selection that will be used
  // for displaying visualizations
  var g = null;

// We will set the domain when the
  // data is processed.
  // @v4 using new scale names
  var xBarScale = d3.scaleLinear()
    .range([0, width]);

// The bar chart display is horizontal
  // so we can use an ordinal scale
  // to get width and y locations.
  // @v4 using new scale type
  var yBarScale = d3.scaleBand()
    .paddingInner(0.08)
    .domain([0, 1, 2])
    .range([0, height - 50], 0.1, 0.1);

// Color is determined just by the index of the bars
  var barColors = { 0: '#008080', 1: '#399785', 2: '#5AAF8C' };

// The histogram display shows the
  // first 30 minutes of data
  // so the range goes from 0 to 30
  // @v4 using new scale name
  var xHistScale = d3.scaleLinear()
    .domain([0, 30])
    .range([0, width - 20]);

// @v4 using new scale name
  var yHistScale = d3.scaleLinear()
    .range([height, 0]);

// The color translation uses this
  // scale to convert the progress
  // through the section into a
  // color value.
  // @v4 using new scale name
  var coughColorScale = d3.scaleLinear()
    .domain([0, 1.0])
    .range(['#008080', 'red']);

// You could probably get fancy and
  // use just one axis, modifying the
  // scale, but I will use two separate
  // ones to keep things easy.
  // @v4 using new axis name
  var xAxisBar = d3.axisBottom()
    .scale(xBarScale);

// @v4 using new axis name
  var xAxisHist = d3.axisBottom()
    .scale(xHistScale)
    .tickFormat(function (d) { return d + ' min'; });

// When scrolling to a new section
  // the activation function for that
  // section is called.
  var activateFunctions = [];
  // If a section has an update function
  // then it is called while scrolling
  // through the section with the current
  // progress through the section.
  var updateFunctions = [];

/**
   * chart
   *
   * @param selection - the current d3 selection(s)
   *  to draw the visualization in. For this
   *  example, we will be drawing it in #vis
   */
  var chart = function (selection) {
    selection.each(function (rawData) {
      // create svg and give it a width and height
      svg = d3.select(this).selectAll('svg').data([wordData]);
      var svgE = svg.enter().append('svg');
      // @v4 use merge to combine enter and existing selection
      svg = svg.merge(svgE);

svg.attr('width', width + margin.left + margin.right);
      svg.attr('height', height + margin.top + margin.bottom);

svg.append('g');

// this group element will be used to contain all
      // other elements.
      g = svg.select('g')
        .attr('transform', 'translate(' + margin.left + ',' + margin.top + ')');

// perform some preprocessing on raw data
      var wordData = getWords(rawData);
      // filter to just include filler words
      var fillerWords = getFillerWords(wordData);

// get the counts of filler words for the
      // bar chart display
      var fillerCounts = groupByWord(fillerWords);
      // set the bar scale's domain
      var countMax = d3.max(fillerCounts, function (d) { return d.value;});
      xBarScale.domain([0, countMax]);

// get aggregated histogram data

var histData = getHistogram(fillerWords);
      // set histogram's domain
      var histMax = d3.max(histData, function (d) { return d.length; });
      yHistScale.domain([0, histMax]);

setupVis(wordData, fillerCounts, histData);

setupSections();
    });
  };

/**
   * setupVis - creates initial elements for all
   * sections of the visualization.
   *
   * @param wordData - data object for each word.
   * @param fillerCounts - nested data that includes
   *  element for each filler word type.
   * @param histData - binned histogram data
   */
  var setupVis = function (wordData, fillerCounts, histData) {
    // axis
    g.append('g')
      .attr('class', 'x axis')
      .attr('transform', 'translate(0,' + height + ')')
      .call(xAxisBar);
    g.select('.x.axis').style('opacity', 0);

// count openvis title
    g.append('text')
      .attr('class', 'title openvis-title')
      .attr('x', width / 2)
      .attr('y', height / 3)
      .text('2013');

g.append('text')
      .attr('class', 'sub-title openvis-title')
      .attr('x', width / 2)
      .attr('y', (height / 3) + (height / 5))
      .text('OpenVis Conf');

g.selectAll('.openvis-title')
      .attr('opacity', 0);

// count filler word count title
    g.append('text')
      .attr('class', 'title count-title highlight')
      .attr('x', width / 2)
      .attr('y', height / 3)
      .text('180');

g.append('text')
      .attr('class', 'sub-title count-title')
      .attr('x', width / 2)
      .attr('y', (height / 3) + (height / 5))
      .text('Filler Words');

g.selectAll('.count-title')
      .attr('opacity', 0);

// square grid
    // @v4 Using .merge here to ensure
    // new and old data have same attrs applied
    var squares = g.selectAll('.square').data(wordData, function (d) { return d.word; });
    var squaresE = squares.enter()
      .append('rect')
      .classed('square', true);
    squares = squares.merge(squaresE)
      .attr('width', squareSize)
      .attr('height', squareSize)
      .attr('fill', '#fff')
      .classed('fill-square', function (d) { return d.filler; })
      .attr('x', function (d) { return d.x;})
      .attr('y', function (d) { return d.y;})
      .attr('opacity', 0);

// barchart
    // @v4 Using .merge here to ensure
    // new and old data have same attrs applied
    var bars = g.selectAll('.bar').data(fillerCounts);
    var barsE = bars.enter()
      .append('rect')
      .attr('class', 'bar');
    bars = bars.merge(barsE)
      .attr('x', 0)
      .attr('y', function (d, i) { return yBarScale(i);})
      .attr('fill', function (d, i) { return barColors[i]; })
      .attr('width', 0)
      .attr('height', yBarScale.bandwidth());

var barText = g.selectAll('.bar-text').data(fillerCounts);
    barText.enter()
      .append('text')
      .attr('class', 'bar-text')
      .text(function (d) { return d.key + '…'; })
      .attr('x', 0)
      .attr('dx', 15)
      .attr('y', function (d, i) { return yBarScale(i);})
      .attr('dy', yBarScale.bandwidth() / 1.2)
      .style('font-size', '110px')
      .attr('fill', 'white')
      .attr('opacity', 0);

// histogram
    // @v4 Using .merge here to ensure
    // new and old data have same attrs applied
    var hist = g.selectAll('.hist').data(histData);
    var histE = hist.enter().append('rect')
      .attr('class', 'hist');
    hist = hist.merge(histE).attr('x', function (d) { return xHistScale(d.x0); })
      .attr('y', height)
      .attr('height', 0)
      .attr('width', xHistScale(histData[0].x1) - xHistScale(histData[0].x0) - 1)
      .attr('fill', barColors[0])
      .attr('opacity', 0);

// cough title
    g.append('text')
      .attr('class', 'sub-title cough cough-title')
      .attr('x', width / 2)
      .attr('y', 60)
      .text('cough')
      .attr('opacity', 0);

// arrowhead from
    // https://logogin.blogspot.com/2013/02/d3js-arrowhead-markers.html
    svg.append('defs').append('marker')
      .attr('id', 'arrowhead')
      .attr('refY', 2)
      .attr('markerWidth', 6)
      .attr('markerHeight', 4)
      .attr('orient', 'auto')
      .append('path')
      .attr('d', 'M 0,0 V 4 L6,2 Z');

g.append('path')
      .attr('class', 'cough cough-arrow')
      .attr('marker-end', 'url(#arrowhead)')
      .attr('d', function () {
        var line = 'M ' + ((width / 2) - 10) + ' ' + 80;
        line += ' l 0 ' + 230;
        return line;
      })
      .attr('opacity', 0);
  };

/**
   * setupSections - each section is activated
   * by a separate function. Here we associate
   * these functions to the sections based on
   * the section's index.
   *
   */
  var setupSections = function () {
    // activateFunctions are called each
    // time the active section changes
    activateFunctions[0] = showTitle;
    activateFunctions[1] = showFillerTitle;
    activateFunctions[2] = showGrid;
    activateFunctions[3] = highlightGrid;
    activateFunctions[4] = showBar;
    activateFunctions[5] = showHistPart;
    activateFunctions[6] = showHistAll;
    activateFunctions[7] = showCough;
    activateFunctions[8] = showHistAll;

// updateFunctions are called while
    // in a particular section to update
    // the scroll progress in that section.
    // Most sections do not need to be updated
    // for all scrolling and so are set to
    // no-op functions.
    for (var i = 0; i < 9; i++) {
      updateFunctions[i] = function () {};
    }
    updateFunctions[7] = updateCough;
  };

/**
   * ACTIVATE FUNCTIONS
   *
   * These will be called their
   * section is scrolled to.
   *
   * General pattern is to ensure
   * all content for the current section
   * is transitioned in, while hiding
   * the content for the previous section
   * as well as the next section (as the
   * user may be scrolling up or down).
   *
   */

/**
   * showTitle - initial title
   *
   * hides: count title
   * (no previous step to hide)
   * shows: intro title
   *
   */
  function showTitle() {
    g.selectAll('.count-title')
      .transition()
      .duration(0)
      .attr('opacity', 0);

g.selectAll('.openvis-title')
      .transition()
      .duration(600)
      .attr('opacity', 1.0);
  }

/**
   * showFillerTitle - filler counts
   *
   * hides: intro title
   * hides: square grid
   * shows: filler count title
   *
   */
  function showFillerTitle() {
    g.selectAll('.openvis-title')
      .transition()
      .duration(0)
      .attr('opacity', 0);

g.selectAll('.square')
      .transition()
      .duration(0)
      .attr('opacity', 0);

g.selectAll('.count-title')
      .transition()
      .duration(600)
      .attr('opacity', 1.0);
  }

/**
   * showGrid - square grid
   *
   * hides: filler count title
   * hides: filler highlight in grid
   * shows: square grid
   *
   */
  function showGrid() {
    g.selectAll('.count-title')
      .transition()
      .duration(0)
      .attr('opacity', 0);

g.selectAll('.square')
      .transition()
      .duration(600)
      .delay(function (d) {
        return 5 * d.row;
      })
      .attr('opacity', 1.0)
      .attr('fill', '#ddd');
  }

/**
   * highlightGrid - show fillers in grid
   *
   * hides: barchart, text and axis
   * shows: square grid and highlighted
   *  filler words. also ensures squares
   *  are moved back to their place in the grid
   */
  function highlightGrid() {
    hideAxis();
    g.selectAll('.bar')
      .transition()
      .duration(600)
      .attr('width', 0);

g.selectAll('.bar-text')
      .transition()
      .duration(0)
      .attr('opacity', 0);

g.selectAll('.square')
      .transition()
      .duration(0)
      .attr('opacity', 1.0)
      .attr('fill', '#ddd');

// use named transition to ensure
    // move happens even if other
    // transitions are interrupted.
    g.selectAll('.fill-square')
      .transition('move-fills')
      .duration(800)
      .attr('x', function (d) {
        return d.x;
      })
      .attr('y', function (d) {
        return d.y;
      });

g.selectAll('.fill-square')
      .transition()
      .duration(800)
      .attr('opacity', 1.0)
      .attr('fill', function (d) { return d.filler ? '#008080' : '#ddd'; });
  }

/**
   * showBar - barchart
   *
   * hides: square grid
   * hides: histogram
   * shows: barchart
   *
   */
  function showBar() {
    // ensure bar axis is set
    showAxis(xAxisBar);

g.selectAll('.square')
      .transition()
      .duration(800)
      .attr('opacity', 0);

g.selectAll('.fill-square')
      .transition()
      .duration(800)
      .attr('x', 0)
      .attr('y', function (d, i) {
        return yBarScale(i % 3) + yBarScale.bandwidth() / 2;
      })
      .transition()
      .duration(0)
      .attr('opacity', 0);

g.selectAll('.hist')
      .transition()
      .duration(600)
      .attr('height', function () { return 0; })
      .attr('y', function () { return height; })
      .style('opacity', 0);

g.selectAll('.bar')
      .transition()
      .delay(function (d, i) { return 300 * (i + 1);})
      .duration(600)
      .attr('width', function (d) { return xBarScale(d.value); });

g.selectAll('.bar-text')
      .transition()
      .duration(600)
      .delay(1200)
      .attr('opacity', 1);
  }

/**
   * showHistPart - shows the first part
   *  of the histogram of filler words
   *
   * hides: barchart
   * hides: last half of histogram
   * shows: first half of histogram
   *
   */
  function showHistPart() {
    // switch the axis to histogram one
    showAxis(xAxisHist);

g.selectAll('.bar-text')
      .transition()
      .duration(0)
      .attr('opacity', 0);

g.selectAll('.bar')
      .transition()
      .duration(600)
      .attr('width', 0);

// here we only show a bar if
    // it is before the 15 minute mark
    g.selectAll('.hist')
      .transition()
      .duration(600)
      .attr('y', function (d) { return (d.x0 < 15) ? yHistScale(d.length) : height; })
      .attr('height', function (d) { return (d.x0 < 15) ? height - yHistScale(d.length) : 0; })
      .style('opacity', function (d) { return (d.x0 < 15) ? 1.0 : 1e-6; });
  }

/**
   * showHistAll - show all histogram
   *
   * hides: cough title and color
   * (previous step is also part of the
   *  histogram, so we don't have to hide
   *  that)
   * shows: all histogram bars
   *
   */
  function showHistAll() {
    // ensure the axis to histogram one
    showAxis(xAxisHist);

g.selectAll('.cough')
      .transition()
      .duration(0)
      .attr('opacity', 0);

// named transition to ensure
    // color change is not clobbered
    g.selectAll('.hist')
      .transition('color')
      .duration(500)
      .style('fill', '#008080');

g.selectAll('.hist')
      .transition()
      .duration(1200)
      .attr('y', function (d) { return yHistScale(d.length); })
      .attr('height', function (d) { return height - yHistScale(d.length); })
      .style('opacity', 1.0);
  }

/**
   * showCough
   *
   * hides: nothing
   * (previous and next sections are histograms
   *  so we don't have to hide much here)
   * shows: histogram
   *
   */
  function showCough() {
    // ensure the axis to histogram one
    showAxis(xAxisHist);

g.selectAll('.hist')
      .transition()
      .duration(600)
      .attr('y', function (d) { return yHistScale(d.length); })
      .attr('height', function (d) { return height - yHistScale(d.length); })
      .style('opacity', 1.0);
  }

/**
   * showAxis - helper function to
   * display particular xAxis
   *
   * @param axis - the axis to show
   *  (xAxisHist or xAxisBar)
   */
  function showAxis(axis) {
    g.select('.x.axis')
      .call(axis)
      .transition().duration(500)
      .style('opacity', 1);
  }

/**
   * hideAxis - helper function
   * to hide the axis
   *
   */
  function hideAxis() {
    g.select('.x.axis')
      .transition().duration(500)
      .style('opacity', 0);
  }

/**
   * UPDATE FUNCTIONS
   *
   * These will be called within a section
   * as the user scrolls through it.
   *
   * We use an immediate transition to
   * update visual elements based on
   * how far the user has scrolled
   *
   */

/**
   * updateCough - increase/decrease
   * cough text and color
   *
   * @param progress - 0.0 - 1.0 -
   *  how far user has scrolled in section
   */
  function updateCough(progress) {
    g.selectAll('.cough')
      .transition()
      .duration(0)
      .attr('opacity', progress);

g.selectAll('.hist')
      .transition('cough')
      .duration(0)
      .style('fill', function (d) {
        return (d.x0 >= 14) ? coughColorScale(progress) : '#008080';
      });
  }

/**
   * DATA FUNCTIONS
   *
   * Used to coerce the data into the
   * formats we need to visualize
   *
   */

/**
   * getWords - maps raw data to
   * array of data objects. There is
   * one data object for each word in the speach
   * data.
   *
   * This function converts some attributes into
   * numbers and adds attributes used in the visualization
   *
   * @param rawData - data read in from file
   */
  function getWords(rawData) {
    return rawData.map(function (d, i) {
      // is this word a filler word?
      d.filler = (d.filler === '1') ? true : false;
      // time in seconds word was spoken
      d.time = +d.time;
      // time in minutes word was spoken
      d.min = Math.floor(d.time / 60);

// positioning for square visual
      // stored here to make it easier
      // to keep track of.
      d.col = i % numPerRow;
      d.x = d.col * (squareSize + squarePad);
      d.row = Math.floor(i / numPerRow);
      d.y = d.row * (squareSize + squarePad);
      return d;
    });
  }

/**
   * getFillerWords - returns array of
   * only filler words
   *
   * @param data - word data from getWords
   */
  function getFillerWords(data) {
    return data.filter(function (d) {return d.filler; });
  }

/**
   * getHistogram - use d3's histogram layout
   * to generate histogram bins for our word data
   *
   * @param data - word data. we use filler words
   *  from getFillerWords
   */
  function getHistogram(data) {
    // only get words from the first 30 minutes
    var thirtyMins = data.filter(function (d) { return d.min < 30; });
    // bin data into 2 minutes chuncks
    // from 0 - 31 minutes
    // @v4 The d3.histogram() produces a significantly different
    // data structure then the old d3.layout.histogram().
    // Take a look at this block:
    // https://bl.ocks.org/mbostock/3048450
    // to inform how you use it. Its different!
    return d3.histogram()
      .thresholds(xHistScale.ticks(10))
      .value(function (d) { return d.min; })(thirtyMins);
  }

/**
   * groupByWord - group words together
   * using nest. Used to get counts for
   * barcharts.
   *
   * @param words
   */
  function groupByWord(words) {
    return d3.nest()
      .key(function (d) { return d.word; })
      .rollup(function (v) { return v.length; })
      .entries(words)
      .sort(function (a, b) {return b.value - a.value;});
  }

/**
   * activate -
   *
   * @param index - index of the activated section
   */
  chart.activate = function (index) {
    activeIndex = index;
    var sign = (activeIndex - lastIndex) < 0 ? -1 : 1;
    var scrolledSections = d3.range(lastIndex + sign, activeIndex + sign, sign);
    scrolledSections.forEach(function (i) {
      activateFunctions[i]();
    });
    lastIndex = activeIndex;
  };

/**
   * update
   *
   * @param index
   * @param progress
   */
  chart.update = function (index, progress) {
    updateFunctions[index](progress);
  };

// return chart function
  return chart;
};

/**
 * display - called once data
 * has been loaded.
 * sets up the scroller and
 * displays the visualization.
 *
 * @param data - loaded tsv data
 */
function display(data) {
  // create a new plot and
  // display it
  var plot = scrollVis();
  d3.select('#vis')
    .datum(data)
    .call(plot);

// setup scroll functionality
  var scroll = scroller()
    .container(d3.select('#graphic'));

// pass in .step selection as the steps
  scroll(d3.selectAll('.step'));

// setup event handling
  scroll.on('active', function (index) {
    // highlight current step text
    d3.selectAll('.step')
      .style('opacity', function (d, i) { return i === index ? 1 : 0.1; });

// activate current section
    plot.activate(index);
  });

scroll.on('progress', function (index, progress) {
    plot.update(index, progress);
  });
}

// load data and display
d3.tsv('words.tsv', display);  
  </script>
</body>
</html>

https://d3js.org/d3.v4.min.js