321, 76, 7
Three coding lines later, the dividend is called for, and the coding, if the dividend is in switch 7431, is:
7431, ——, 7
We can send the quotient, when ready, into any desired counter Q by the following two lines of coding:
—— —— 642
876 Q ——
In the same way as with multiplication, we can insert a number of coding lines in between the dividend line and the first quotient line.
Both multiplication and division are carried out in the same unit of the machine, the multiply-divide unit. The machine first constructs a table of the multiples of the multiplicand or divisor: 1 times, 2 times, 3 times, ···, 9 times. In multiplication this table is then used by selecting multiples according to the digits of the multiplier one after another. In division the table is used by comparing multiples of the divisor against the dividend and successive remainders, finding which will go and which will not. Since the numbers in the machine are normally of 15 to 23 digits, any particular multiple will be used, on the average, several times, and so this process is relatively efficient. Actually the multiplicand and the divisor go into the same counter. Division, however, has the code 76 and multiplication the code 761, and so the difference is essentially an operation code not in the third or C field.
Consulting a Table
When we desire the machine to consult a table of values (i.e., a function—[see Supplement 2]), we punch the table with its arguments and function values on a tape, and we put the tape on a value tape feed mechanism. The instruction to the machine may be: