# Product from max to min [closed]

Product[f[i], {i, 1, 4}]


gives us

f[1] f[2] f[3] f[4]


Is there any way I can take the product it will give something following

f[4] f[3] f[2] f[1]


I need it for matrix multiplication in reverse order.

• mybe with NonCommutativeMultiply @@ (Reverse[List @@ (f[1] f[2] f[3] f[4])]) /. NonCommutativeMultiply[A_, B___] :> HoldForm[Times[A, B]] ? – user49047 Sep 3 '19 at 14:58
• What about Dot@@Table[f[i],{i,4,1,-1}]? (Note the step size of -1 to go backwards) – Lukas Lang Sep 3 '19 at 15:01
• @user49047 worked Thanks. – Muhammad Ali Sep 3 '19 at 16:51

You can get a list of the values using Map (i.e., shortcut /@)
f[#] & /@ Range[4, 1, -1]

To get the Dot product of the f's you can Apply (i.e., shortcut @@) the Dot function:
Dot @@ (f[#] & /@ Range[4, 1, -1])
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