#Fuzzy Octo Guacamole, 7 bytes _{non-competing, FOG is newer than the challenge}

EZO@pZE

This is the equivalent of a function in FOG. It assumes the input is on the stack. This can be assigned to a function by the code "EZO@pZE""f"o, where f is any single-char name you want to assign. Then use it like any other command. Example: "EZO@pZE"'f'o^f.

Explanation:

EZO@pZE
E       # Push E (2.718....)
 Z      # Reverse stack (it is now [e, input])
  O     # log(x, y) which is ln(input)
   @    # Exit. (implicit output) Nothing after this gets run.
    p   # x^y (power function)
     Z  # Reverse stack
      E # Push E.

Reversed:

EZp@OZE
E       # Push E (2.718....)
 Z      # Reverse stack (it is now [e, input])
  O     # x^y (power function)
   @    # Exit. (implicit output) Nothing after this gets run.
    p   # log(x, y) which is ln(input)
     Z  # Reverse stack
      E # Push E.

Fuzzy Octo Guacamole, 7 bytes

_{non-competing, FOG is newer than the challenge}

EZO@pZE

This is the equivalent of a function in FOG. It assumes the input is on the stack. This can be assigned to a function by the code "EZO@pZE""f"o, where f is any single-char name you want to assign. Then use it like any other command. Example: "EZO@pZE"'f'o^f.

Explanation:

EZO@pZE
E       # Push E (2.718....)
 Z      # Reverse stack (it is now [e, input])
  O     # log(x, y) which is ln(input)
   @    # Exit. (implicit output) Nothing after this gets run.
    p   # x^y (power function)
     Z  # Reverse stack
      E # Push E.

Reversed:

EZp@OZE
E       # Push E (2.718....)
 Z      # Reverse stack (it is now [e, input])
  O     # x^y (power function)
   @    # Exit. (implicit output) Nothing after this gets run.
    p   # log(x, y) which is ln(input)
     Z  # Reverse stack
      E # Push E.

#Fuzzy Octo Guacamole, 7 bytes _{non-competing, FOG is newer than the challenge}

EZO@pZE

This is the equivalent of a function in FOG. It assumes the input is on the stack.

Explanation:

EZO@pZE
E       # Push E (2.718....)
 Z      # Reverse stack (it is now [e, input])
  O     # log(x, y) which is ln(input)
   @    # Exit. (implicit output) Nothing after this gets run.
    p   # x^y (power function)
     Z  # Reverse stack
      E # Push E.

Reversed:

EZp@OZE
E       # Push E (2.718....)
 Z      # Reverse stack (it is now [e, input])
  O     # x^y (power function)
   @    # Exit. (implicit output) Nothing after this gets run.
    p   # log(x, y) which is ln(input)
     Z  # Reverse stack
      E # Push E.

#Fuzzy Octo Guacamole, 7 bytes _{non-competing, FOG is newer than the challenge}

EZO@pZE

This is the equivalent of a function in FOG. It assumes the input is on the stack. This can be assigned to a function by the code "EZO@pZE""f"o, where f is any single-char name you want to assign. Then use it like any other command. Example: "EZO@pZE"'f'o^f.

Explanation:

EZO@pZE
E       # Push E (2.718....)
 Z      # Reverse stack (it is now [e, input])
  O     # log(x, y) which is ln(input)
   @    # Exit. (implicit output) Nothing after this gets run.
    p   # x^y (power function)
     Z  # Reverse stack
      E # Push E.

Reversed:

EZp@OZE
E       # Push E (2.718....)
 Z      # Reverse stack (it is now [e, input])
  O     # x^y (power function)
   @    # Exit. (implicit output) Nothing after this gets run.
    p   # log(x, y) which is ln(input)
     Z  # Reverse stack
      E # Push E.