It depends on how you want to use them. If you want to have three floats to pick origin points, you don't need to use the second option just to save lines. Stick with the first one, more organized and easy to understand.
I guess you've chosen a bad example to explain your question. There are no difference in the final code, just how you use them, as I said before...
PHP Code:
pev(id, pev_origin, __fl_gOrigin[id])
console_print(id, "%.1f %.1f %.1f", __fl_gOrigin[id][0], __fl_gOrigin[id][1], __fl_gOrigin[id][2])
#2
PHP Code:
pev(id, pev_origin, __fl_gOrigin[id][0])
console_print(id, "%.1f %.1f %.1f", __fl_gOrigin[id][0][0], __fl_gOrigin[id][0][1], __fl_gOrigin[id][0][2])
pev(id, pev_origin, __fl_gOrigin[id][1])
console_print(id, "%.1f %.1f %.1f", __fl_gOrigin[id][1][0], __fl_gOrigin[id][1][1], __fl_gOrigin[id][1][2])
pev(id, pev_origin, __fl_gOrigin[id][2])
console_print(id, "%.1f %.1f %.1f", __fl_gOrigin[id][2][0], __fl_gOrigin[id][2][1], __fl_gOrigin[id][2][2])
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