add percentage to results output

This commit is contained in:
Steven Polley 2020-11-14 10:25:49 -07:00
parent e4646c4b62
commit 7ce4439bd2
2 changed files with 24 additions and 11 deletions

View File

@ -6,14 +6,25 @@ This was a test to determine if random numbers follow [Benford's Law](https://en
With One-Hundred-Million samples of random numbers between 0 and 9,999,999,999,999,999, the number of leading digits was the following: With One-Hundred-Million samples of random numbers between 0 and 9,999,999,999,999,999, the number of leading digits was the following:
1: 11105630 ```shell
2: 11110535 $ ./benfords-law.exe
3: 11112084 2020/11/14 10:24:18 generating numbers...
4: 11113667 2020/11/14 10:24:19 18% completed generating and analyzing samples
5: 11120216 2020/11/14 10:24:20 37% completed generating and analyzing samples
6: 11106549 2020/11/14 10:24:21 56% completed generating and analyzing samples
7: 11108623 2020/11/14 10:24:22 75% completed generating and analyzing samples
8: 11114813 2020/11/14 10:24:23 93% completed generating and analyzing samples
9: 11107883 2020/11/14 10:24:24 done.
1: 1108503 (11.085030%)
2: 1111584 (11.115840%)
3: 1111726 (11.117260%)
4: 1111122 (11.111220%)
5: 1110443 (11.104430%)
6: 1111248 (11.112480%)
7: 1111496 (11.114960%)
8: 1111777 (11.117770%)
9: 1112101 (11.121010%)
Press 'Enter' to continue...
```
This shows that Benford's law only works when the data is not random, such as natural data gathered in real life. This is because natural data is generated following a power law, which is common in nature. This shows that Benford's law only works when the data is not random, such as natural data gathered in real life. This is because natural data is generated following a power law, which is common in nature.

View File

@ -27,7 +27,7 @@ func main() {
for { for {
<-statusTicker.C <-statusTicker.C
percentCompleted := (currentSample * 100) / numSamples percentCompleted := (currentSample * 100) / numSamples
log.Printf("%d %% completed generating and analyzing samples", percentCompleted) log.Printf("%d%% completed generating and analyzing samples", percentCompleted)
} }
}() }()
@ -48,7 +48,7 @@ func main() {
// output results // output results
for digitMinusOne, count := range results { for digitMinusOne, count := range results {
fmt.Printf("%d: %d\n", digitMinusOne+1, count) fmt.Printf("%d: %d (%f%%)\n", digitMinusOne+1, count, float64(count*100)/float64(numSamples))
} }
fmt.Print("Press 'Enter' to continue...") fmt.Print("Press 'Enter' to continue...")
@ -61,10 +61,12 @@ func generatorWorker(returnChannel chan int) {
} }
} }
// firstDigit returns the first/leftmost digit of the base10 representation of an integer
func firstDigit(x int) int { func firstDigit(x int) int {
return int(math.Abs(float64(x)) / math.Pow(10, float64(numDigits(x)-1))) return int(math.Abs(float64(x)) / math.Pow(10, float64(numDigits(x)-1)))
} }
// numDigits returns the number of digits
func numDigits(x int) int { func numDigits(x int) int {
if x == 0 { if x == 0 {
return 1 return 1