It will be better if you could clarify it.
Because if you want to change the number of columns you just need to change its number in place which determinates them.
Please, take a look at this example: http://jsfiddle.net/howb6e1x/
There is no such feature, unfortunately.
That you could try is to create a custom scenario.
For example, it is possible to create the jqxRibbon which is placed on the bottom of the jqxGrid.
Each new tab of the jqxRibbon will show jqxGrids with different columns.
Or another scenario, the jqxGrid with jqxToolBar under the table or in its statusbar.
But you should create this with your custom logic.