How do I tell d3 to not repeat values in ticks?

I needed mine to be dynamic, this worked for me: [Version 4]

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

 var yAxis = d3.axisLeft()
        .scale(y)
        .tickFormat(d3.format("%d"));

      // Reset the axes domains with new data
      y.domain([0, d3.max(data, function (d) { return d.value; })]);


  if (y.domain() [1] < 10) {
            yAxis.ticks(y.domain()[1])

            // 2 ticks
            //yAxis.tickValues(y.domain());
        }

        // Add the y-axis with a transition
        yAxisG
          .transition()
            .duration(500)
            .call(yAxis);