Conditional if inside expression

[#1]

I have a field that indicates whether the value of another column is percentage (%) or unit (U) if % format the value of the expression in percentage format or in number with a decimal point. It has to do with if inside the expression?

[#2 · Accepted solution]

See attached for a small example.

Hope it helps.

[#3]

I try to make this in expression:

if(UNITY = '%', num(Sum (VALUE),'#.##0,00%'),

if(UNITY <> '%', num(Sum (VALUE),'#.##0,00')))

But not working...