Finding the integral of f(x,y,z) = 1/(1-cos(x)cos(y)cos(z))*(1/pi^3)
  N =      1000000
  True value:    1.3932039737701416     
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  Plain Monte Carlo: 
 Integral =    1.4079604768314862     
 Error =   1.31577800959158889E-002
 Integral fejl =   1.47565030613445725E-002
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  Quasi-Random: 
 Integral =    1.4010409688533298     
 Error =   1.10869412363872478E-002
 Integral fejl =   7.83699508318824734E-003
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  Stratified: 
           2
           2
           2
           2
           2
           2
           2
           2
           2
           2
           2
           2
           2
           2
           2
           2
 Integral =    1.3921843112768812     
 Error =   8.71288825522716710E-004
 Integral fejl =   1.01966249326035374E-003
 ==================================