JavaScriptCollection
diff --git a/‎api/index.markdown‎
Lines changed: 13 additions & 8 deletions b/‎api/index.markdown‎
Lines changed: 13 additions & 8 deletions
@@ -154,34 +154,39 @@ tickFormat), log (invert, rangeRound, interpolate, ticks, tickFormat), pow
 category20b, category20c, quantile (quantiles), quantize.
 
 ####`d3.scale.linear`
-Map the domain to the range with a linear function.
+Map the domain (a number) to the range (a number) with a linear function.
     s = d3.scale.linear().domain([0,100]).range([10,20])
     s(50) == 15
 
 ####`d3.scale.pow`
-Map the domain to the range with a power function
+Map the domain (a number) to the range (a number) with a power function.
     s = d3.scale.pow().domain([0,10]).range([0,10]).exponent(2)
     s(5) == 2.5
 
 ####`d3.scale.sqrt`
-Map the domain to the range with a square root function. Equivalent to pow.exponent(0.5)
+Map the domain (a number) to the range (a number) with a square root function. Equivalent to pow.exponent(0.5)
 
 ####`d3.scale.log`
-Map the domain to the range with a logarithmic function.
+Map the domain (a number) to the range (a number) with a logarithmic function.
 
     s = d3.scale.log().domain([1,10]).range([0,10])
     s(5) == 6.9897000433601875
 
-####`d3.scale.category`
-
 ####`d3.scale.ordinal`
+Map the domain (an element of a set) to the range (an element of a set).
+    s = d3.scale.ordinal().domain(["a", "b", "c"]).range(["one", "two", "three"])
+    s("b") == "two"
 
-####`d3.scale.quantile`
+####`d3.scale.category10`, `d3.scale.category20`, `d3.scale.category20b`, `d3.scale.category20c`
+A set of ordinal scales that map the domain to a range of 10 or 20 colours defined by a <a href="http://colorbrewer.org/">ColorBrewer</a> scale.
 
 ####`d3.scale.quantize`
 
-####`d3.scale.scale
+Map the domain (a number) to the range (an element of a set).
+    s = d3.scale.quantize().domain([0,4]).range(["zero", "one", "two", "three"])
+    s(2.7) == "two"
 
+####`d3.scale.quantile`