Tratamento das celas baleiras
In older versions of the software, empty cells were forced to numeric 0 in some contexts and to empty string in others, except in direct comparison where =A1=0 and =A1="" both resulted in TRUE if A1 was empty. Emptiness now is inherited until used, so both =VLOOKUP(...)=0 and =VLOOKUP(...)="" give TRUE if the lookup resulted in an empty cell being returned.
A simple reference to an empty cell is still displayed as numeric 0 but is not necessarily of type numeric anymore, so also comparisons with the referencing cell work as expected.
Nos exemplos seguintes, A1 contén un número, B1 está baleira e C1 contén a referencia a B1:
A1: 1 B1: <Baleira> C1: =B1 (mostra 0)
=B1=0 => VERDADEIRO
=B1="" => VERDADEIRO
=C1=0 => VERDADEIRO
=C1="" => VERDADEIRO (anteriormente era FALSO)
=É.NÚM(B1) => FALSO
=ISNUMBER(C1) => FALSE (previously was TRUE)
=ISNUMBER(VLOOKUP(1;A1:C1;2)) => FALSE (B1)
=ISNUMBER(VLOOKUP(1;A1:C1;3)) => FALSE (C1, previously was TRUE)
=ISTEXT(B1) => FALSE
=ISTEXT(C1) => FALSE
=ISTEXT(VLOOKUP(1;A1:C1;2)) => FALSE (B1, previously was TRUE)
=ISTEXT(VLOOKUP(1;A1:C1;3)) => FALSE (C1)
=ISBLANK(B1) => TRUE
=ISBLANK(C1) => FALSE
=ISBLANK(VLOOKUP(1;A1:C1;2)) => TRUE (B1, previously was FALSE)
=ISBLANK(VLOOKUP(1;A1:C1;3)) => FALSE (C1)
Note that Microsoft Excel behaves different and always returns a number as the result of a reference to an empty cell or a formula cell with the result of an empty cell. For example:
A1: <Empty>
B1: =A1 => mostra 0, mais é só unha referencia a unha cela baleira
=É.NÚM(B1) => FALSO
=ÉTEXTO(A1) => FALSO
=B1=0 => VERDADEIRO
=B1="" => VERDADEIRO
=ÉNUMERO(B1) => FALSO (Microsoft Excel: VERDADEIRO)
=ÉTEXTO(B1) => FALSO
=B1=0 => VERDADEIRO
=B1="" => VERDADEIRO (Microsoft Excel: FALSO)
C1: =PROCV(…) con resultado de cela baleira => mostra baleira (Microsoft Excel: mostra 0)
=ÉNUMERO(PROCV(...)) => FALSO
=ÉTEXTO(PROCV(...)) => FALSO
=ÉNUMERO(C1) => FALSO (Microsoft Excel: VERDADEIRO)
=ÉTEXTO(C1) => FALSO