I was looking through my box of relics that has old hardware, software, books, and unearthed this DOS 6.22 diskette I was looking for. I have another box in the attic with a Kaypro CP/M, MacIntosh SE, and a PET Commodore with a joystick I played Golf and other games. Is any of this old stuff have collectible value?
in 2012 (just checked my records and I also found the eBay listing photo!) I e-bayed a boxed and unused multiple floppy disk Windows v1.0 for an Olivetti M24. I netted £133 from an italian buyer.
in 2012 (just checked my records and I also found the eBay listing photo!) I e-bayed a boxed and unused multiple floppy disk Windows v1.0 for an Olivetti M24. I netted £133 from an italian buyer.
Ah, that has sentimental value to that buyer because Olivetti was/is an Italian company. In 1984 I owned an AT&T 6300 PC, which was an Olivetti OEM. I was happy with its performance. I also used a MacIntosh with a Laserwriter printer, which I still own, for printing pretty WYSIWYG documents. My employers were impressed, as back in those days most people were using WordStar, Wang, Lanier with daisywheel printers.
Showcase your relics? Hell, I've got my picture as my avatar. How much more showcasing do we need? (Yes, I HAVE been accused of being a relic and a dinosaur.)
To me, Access 97 was the first version that provided robust VBA for building functionally rich apps. I include several standard modules in all my Access apps that were built with Access 97 by Ken Getz (RIP).
Showcase your relics? Hell, I've got my picture as my avatar. How much more showcasing do we need? (Yes, I HAVE been accused of being a relic and a dinosaur.)
I also conserved the yellow colored punched paper tape that stores the first BASIC program I wrote in high school. A program for finding Perfect Numbers.
We had an old Teletype Model 33 terminal with a 300 baud dialup modem that connected to a GE Mark II Timesharing System in Dartmouth, MA.
The terminal had a paper tape reader/puncher which would read our programs to execute them.
Code:
100 REM FIND PERFECT NUMBERS BETWEEN 2 AND 1E+5
110 REM NORTHFIELD MOUNT HERMON SCHOOL, GILL, MASSACHUSETTS, 1973.
120 REM
130 LET START = 2
140 LET FINISH = 1E+5
150 REM
160 FOR N = START TO FINISH
170 LET SUM = 1
180 FOR I = 2 TO SQR(N)
190 IF N / I = INT(N / I) THEN GOTO 210
200 GOTO 230
210 LET SUM = SUM + I
220 IF N / I <> I THEN LET SUM = SUM + N / I
230 NEXT I
240 IF SUM = N THEN PRINT N;" IS A PERFECT NUMBER"
250 NEXT N
260 END
I rewrote the code in VBA and use it to benchmark CPU's. It has nested loops and is very CPU intensive.
How many seconds does it take for your computer to find perfect numbers between 2 and 100,000?
Keep in mind that the program has to find each number's proper divisors that are whole integers and then has to add those divisors up to see if the sum equals the number being evaluated. The sum of proper divisors of a number is called its aliquot sum, so a perfect number is one that is equal to its aliquot sum. As the number being checked gets higher, the more divisors it has to evaluate to see if they're whole numbers. You may want to shorten the range below 100,000, unless you have a super fast CPU. The first seven perfect numbers are 6, 28, 496, 8,128, 33,550,336, 8,589,869,056, and 137,438,691,328.
Code:
Option Compare Database
Option Explicit
' Function to check if a number is a perfect
Public Function IsPerfectNumber(ByVal NumberToCheck As Long) As Boolean
Dim SumOfDivisors As Long
Dim i As Long
' A perfect number must be a positive integer greater than 1
If NumberToCheck <= 1 Then
IsPerfectNumber = False
Exit Function
End If
SumOfDivisors = 1 ' Start with 1, as 1 is always a divisor
' Loop through potential divisors up to half of the number
For i = 2 To NumberToCheck / 2
If NumberToCheck Mod i = 0 Then
SumOfDivisors = SumOfDivisors + i
End If
Next i
' If the sum of proper divisors equals the number, it's a perfect number
If SumOfDivisors = NumberToCheck Then
IsPerfectNumber = True
Else
IsPerfectNumber = False
End If
End Function
' Sub-procedure to find and display perfect numbers
Public Sub FindPerfectNumbers()
Dim StartRange As Long
Dim EndRange As Long
Dim CurrentNumber As Long
Dim PerfectNumbersFound As String
' Get the range from the user (e.g., using InputBox)
StartRange = InputBox("Enter the starting number for the search:", "Perfect Number Search", 2)
EndRange = InputBox("Enter the ending number for the search:", "Perfect Number Search", 100000)
If StartRange > EndRange Then
MsgBox "Starting number cannot be greater than the ending number.", vbCritical
Exit Sub
End If
PerfectNumbersFound = "Perfect Numbers found in the range " & StartRange & " to " & EndRange & ":" & vbCrLf
' Iterate through the specified range
For CurrentNumber = StartRange To EndRange
If IsPerfectNumber(CurrentNumber) Then
PerfectNumbersFound = PerfectNumbersFound & CurrentNumber & vbCrLf
End If
Next CurrentNumber
' Display the results
If InStr(PerfectNumbersFound, vbCrLf & vbCrLf) > 0 Then ' Check if any perfect numbers were found
MsgBox PerfectNumbersFound, vbInformation, "Perfect Numbers"
Else
MsgBox "No perfect numbers found in the specified range.", vbInformation, "Perfect Numbers"
End If
End Sub
