HP 12C Platinum Owner's Handbook Manual page 81

Section 7: Mathematics and Number-Alteration Functions
Integer. Pressing gÑ replaces the number in the display by its integer
portion – that is, it replaces each digit to the right of the decimal point by 0. The
number is changed inside the calculator as well as in the display. The original
number can be recalled to the display by pressing gF.
Fractional. Pressing gT replaces the number in the display by its fractional
portion – that is, it replaces all digits to the left of the decimal point by 0. Like
Ñ, T changes the number inside the calculator as well as its displayed
version. The original number can be recalled to the display by pressing gF.
All of the above functions are used basically in the same way. For example, to
find the reciprocal of 0.258:
Keystrokes
.258
y
Any of the above functions can be done with a number in the display resulting
from a previous calculation, as well as with a number you have just keyed in.
Keystrokes (RPN mode)
fCLEAR X
fB
fX
gÑ
gF
gT
Display
Keys the number into the display.
0.258
The reciprocal of 0.258, the original
3.88
number.
Display
3875968992 Displays all 10 digits of the number
inside the calculator.
Display returns to normal format
3.88
when X key is released.
The number now in the display
3.88
appears the same as before, but ...
3880000000 Displaying all 10 digits of the
number inside the calculator shows
B has changed the number to
match its displayed version.
Display returns to normal format.
3.88
The integer portion of the number
3.00
previously displayed.
Recalls the original number to the
3.88
display.
The fractional portion of the
0.88
number previously displayed.
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