Raise e to a power

exp x     exp[x]

Where

returns as a float ex, or null if x is null.

q)exp 1
2.718282

q)exp 0.5
1.648721

q)exp -4.2 0 0.1 0n 0w
0.01499558 1 1.105171 0n 0w

q)exp 00:00:00 00:00:12 12:00:00
1 162754.8 0w