Here is a script that will color the column weight's first 10 rows in the data table.
names default to here(1);
dt=Open("$SAMPLE_DATA/big class.jmp");
// Set the gradient list of colors
colorList = {-2768895, -5530606, -6582759, -8094941, -9147350, -10462158, -11514567, -12237762,
-13344414, -14575206};
// Color first 10 rows
// find the range
weightMin= col min(if(Row()<=10,:weight,.));
weightMax= col max(if(Row()<=10,:weight,.));
weightInc= (weightMax-weightmin)/10;
// Loop across and set the colors
For(i=1,i<=10,i++,
Bin=floor((:weight[i]-weightMin)/weightInc)+1;
if(Bin>10,Bin=10);
:weight << color cells( colorList[bin],i)
);
To understand all of the concepts behind the colors in JMP, you need to read the documentation in the Scripting Guide on Specifying Colors
Jim