I messed up.
http://fourier.eng.hmc.edu/e85_old/lectures/arithmetic_html/node9.html (http://fourier.eng.hmc.edu/e85_old/lectures/arithmetic_html/node9.html)
I messed up again.
I think it is:
111011
111100
_______
000000
000000
111011
111011
111011
111011
_______
1111 0111100100
I read my code
left to right
first I count the ones
second I count the zeros
third I count the ones' segments
forth I count the zeros' segments
.
Please let me know why I am wrong.
My programmer calculator says -5 * -4 is -1. Weird.
Due to my calculator I think I need to take 15864 - (my code) to correct the result.
(http://img600.imageshack.us/img600/9704/6r5n.png)
Do 4*5 instead and then take 2's complement. The thing marked in yellow should be your result. EDIT: don't take 2's complement...
For binary multiplications I.
would suggest this algorithm http://en.wikipedia.org/wiki/Multiplication_algorithm#Peasant_or_binary_multiplication
In fact it is just the same as long multiplication though.
Quote from: gelatine1 link=topic=2708.msg28757#msg28757 date=1386674654 #delete image from above
Do 4*5 instead and then take 2's complement. The thing marked in yellow should be your result. EDIT: don't take 2's complement...
For binary multiplications I.
would suggest this algorithm http://en.wikipedia.org/wiki/Multiplication_algorithm#Peasant_or_binary_multiplication (http://en.wikipedia.org/wiki/Multiplication_algorithm#Peasant_or_binary_multiplication)
In fact it is just the same as long multiplication though.
In my system's calculator the number I found for -20 doesn't matter after many ghost errors. What you showed me I do not understand.
Should we explain long multiplication to each other on smaller number scales?
Should we use the decimal point in our long multiplication?
Please move this to the romper.