How to place redstone using Command Blocks

The are two reasons why this command probably isn't working:

• First, you can't have decimals with the co-ordinates of this particular Minecraft block. They have to be whole numbers not decimals. Try placing a block where you want the redstone to be, look at it, press F3. You will see the co-ordinates of the block in the top right hand side. (See 'looking at'). Destroy the block and use these co-ords in the command.
• Secondly, the id for redstone dust (the block) is minecraft:redstone_wire, as the inventory item is minecraft:redstone

Adding on to Angus' answer, there are also 16 different states for redstone wire, which you can specify using the data value.

This is because: 2^4 = 16-1 = 0 to 15.