[B4X] Today - Pi Day

[Star-Dust]

Today March 14 (3/14) is the day of the Greek Pi ù

(https://en.wikipedia.org/wiki/Pi_Day)

3,14159 26535 89793 23846 26433 83279 50288 41971 69399 37510 58209 74944 59230 78164 06286 20899 86280 34825 34211 70679…

 

[Star-Dust]

Some B4X methods to calculate it

1) Formulas di Leibniz

Dim N As Int = 1000 ' The greater the value, the greater the precision
Dim PiGreek As Double = 1
 
For i=1 To N
    PiGreek=PiGreek+Power(-1,i)/(2*i+1)
Next
 
Log(4*PiGreek)

2) Formulas di Machin

Dim PiGreek As Double = 4*ATan(1/5)-ATan(1/239)

Log(4*PiGreek)

3) Formulas di Wallis

Dim N As Int = 1000
Dim PiGreek As Double = 1

For i=1 To N
    PiGreek=PiGreek*((i*2)/((i-1)*2+1))*((i*2)/((i-1)*2+3))
Next

Log(2*PiGreek)

 

[Erel]

Sub AppStart (Args() As String)
   Dim CountIn As Int
   Dim Total As Int = 100000000
   For i = 0 To Total - 1
       Dim r1 As Int = Rnd(0, 0x7fffffff)
       Dim r2 As Int = Rnd(0, 0x7fffffff)
       Dim x As Double = r1 / 0x7fffffff
       Dim y As Double = r2 / 0x7fffffff
       Dim distance2 As Double = Power(x - 0.5, 2) + Power(y - 0.5, 2)
       If distance2 <= 0.25 Then CountIn = CountIn + 1
   Next
   Log(CountIn / Total / 0.25)
End Sub

 

[Star-Dust]

Formulas di Basel

Dim N As Int = 1000
Dim PiGreek As Double = 0
   
For i=1 To N
        PiGreek=PiGreek+1/Power(i,2)
Next
   
Log(Sqrt(PiGreek*6))

 

[MarkusR]

simplified ~ 22/7

 

[Star-Dust]

simplified ~ 22/7

There is a difference between an approximation and a calculation.

22/7= 3.1428571429
PI Gr= 3,1415926535 89793

 

[MarkusR]

There is a difference between an approximation and a calculation.
22/7= 3.1428571429
PI Gr= 3,1415926535 89793

yes but it works if u have a sin / cos method with radiant input 22/7/180 (angle in radians) and you will just move a sprite along this direction.

https://en.wikipedia.org/wiki/Radian

 

[Star-Dust]

I'll talk about it with Euler

 

[thetahsk]

Dim fraction_PI  As Double = 3 + 1/(7 + 1/(15 + 1/(1 + 1/(292 + 1/(1 + 1/(1 + 1/(1 + 1/(2 + 1/(1 + 1/(3 + 1/(1 + 1/(14 + 1/(2 + 1/(1 + 1/(1 + 1/(2 + 1/(2 + 1/(2 + 1/(2 + 1/(1 + 1))))))))))))))))))))

from

https://www.wolframalpha.com/input/?i=continued+fraction+pi&lk=2

 

[Star-Dust]

Today March 14 2026 is the day of the Greek Pi

There is a mathematical relationship that links pi to other mathematical constants and which design the universe and creation

Euler's identity is a formula that deals with powers and complex numbers by putting together some of the most important and famous mathematical constants. And it is precisely thanks to its ability to inextricably link the following numbers that many scholars consider it one of the most beautiful formulas in mathematics