Delete erfc.py

modules/erfc.py

@@ -1,212 +0,0 @@
-from math import *
-
-tiny= 1e-300
-half=  5.00000000000000000000e-01
-one =  1.00000000000000000000e+00
-two =  2.00000000000000000000e+00
-erx =  8.45062911510467529297e-01
-
-## Coefficients for approximation to  erf on [0,0.84375]
-
-efx =  1.28379167095512586316e-01
-efx8=  1.02703333676410069053e+00
-pp0  =  1.28379167095512558561e-01
-pp1  = -3.25042107247001499370e-01
-pp2  = -2.84817495755985104766e-02
-pp3  = -5.77027029648944159157e-03
-pp4  = -2.37630166566501626084e-05
-qq1  =  3.97917223959155352819e-01
-qq2  =  6.50222499887672944485e-02
-qq3  =  5.08130628187576562776e-03
-qq4  =  1.32494738004321644526e-04
-qq5  = -3.96022827877536812320e-06
-
-def erf1(x):
-    '''erf(x) for x in [0,0.84375]'''
-    e, i = frexp(x)
-    if abs(i)>28:
-        if abs(i)>57:
-            return 0.125*(8.0*x+efx8*x)
-        return x + efx*x
-    z = x*x
-    r = pp0+z*(pp1+z*(pp2+z*(pp3+z*pp4)))
-    s = one+z*(qq1+z*(qq2+z*(qq3+z*(qq4+z*qq5))))
-    y = r/s
-    return x + x*y
-
-def erfc1(x):
-    '''erfc(x)for x in [0,0.84375]'''
-    e,i = frexp(x)
-    if abs(i)>56:
-        return one-x
-    z = x*x
-    r = pp0+z*(pp1+z*(pp2+z*(pp3+z*pp4)))
-    s = one+z*(qq1+z*(qq2+z*(qq3+z*(qq4+z*qq5))))
-    y = r/s
-    if (x<0.25):
-        return one-(x+x*y)
-    else:
-        r = x*y
-        r += (x-half)
-        return half - r
-
-## Coefficients for approximation to  erf  in [0.84375,1.25] 
-
-pa0  = -2.36211856075265944077e-03
-pa1  =  4.14856118683748331666e-01
-pa2  = -3.72207876035701323847e-01
-pa3  =  3.18346619901161753674e-01
-pa4  = -1.10894694282396677476e-01
-pa5  =  3.54783043256182359371e-02
-pa6  = -2.16637559486879084300e-03
-qa1  =  1.06420880400844228286e-01
-qa2  =  5.40397917702171048937e-01
-qa3  =  7.18286544141962662868e-02
-qa4  =  1.26171219808761642112e-01
-qa5  =  1.36370839120290507362e-02
-qa6  =  1.19844998467991074170e-02
-
-def erf2(x):
-    '''erf(x) for x in [0.84375,1.25]'''
-    s = fabs(x)-one
-    P = pa0+s*(pa1+s*(pa2+s*(pa3+s*(pa4+s*(pa5+s*pa6)))))
-    Q = one+s*(qa1+s*(qa2+s*(qa3+s*(qa4+s*(qa5+s*qa6)))))
-    if x>=0:
-        return erx + P/Q
-    return -erx - P/Q
-
-def erfc2(x):
-    '''erfc(x) for x in [0.84375, 1.25]'''
-    return one-erf2(x)
-
-## Coefficients for approximation to  erfc in [1.25,1/0.35]
-
-ra0  = -9.86494403484714822705e-03
-ra1  = -6.93858572707181764372e-01
-ra2  = -1.05586262253232909814e+01
-ra3  = -6.23753324503260060396e+01
-ra4  = -1.62396669462573470355e+02
-ra5  = -1.84605092906711035994e+02
-ra6  = -8.12874355063065934246e+01
-ra7  = -9.81432934416914548592e+00
-sa1  =  1.96512716674392571292e+01
-sa2  =  1.37657754143519042600e+02
-sa3  =  4.34565877475229228821e+02
-sa4  =  6.45387271733267880336e+02
-sa5  =  4.29008140027567833386e+02
-sa6  =  1.08635005541779435134e+02
-sa7  =  6.57024977031928170135e+00
-sa8  = -6.04244152148580987438e-02
-
-def erf3(x):
-    '''erf(x) for x in [1.25,2.857142]'''
-    x0=x
-    x = fabs(x)
-    s = one/(x*x)
-    R=ra0+s*(ra1+s*(ra2+s*(ra3+s*(ra4+s*(ra5+s*(ra6+s*ra7))))))
-    S=one+s*(sa1+s*(sa2+s*(sa3+s*(sa4+s*(sa5+s*(sa6+s*(sa7+s*sa8)))))))
-    z = ldexp(x0,0)
-    r = exp(-z*z-0.5625)*exp((z-x)*(z+x)+R/S)
-    if(x0>=0):
-        return one-r/x
-    else:
-        return  r/x-one;
-
-def erfc3(x):
-    '''erfc(x) for x in [1.25,1/0.35]'''
-    return one-erf3(x)
-
-## Coefficients for approximation to  erfc in [1/.35,28]
-
-rb0  = -9.86494292470009928597e-03
-rb1  = -7.99283237680523006574e-01
-rb2  = -1.77579549177547519889e+01
-rb3  = -1.60636384855821916062e+02
-rb4  = -6.37566443368389627722e+02
-rb5  = -1.02509513161107724954e+03
-rb6  = -4.83519191608651397019e+02
-sb1  =  3.03380607434824582924e+01
-sb2  =  3.25792512996573918826e+02
-sb3  =  1.53672958608443695994e+03
-sb4  =  3.19985821950859553908e+03
-sb5  =  2.55305040643316442583e+03
-sb6  =  4.74528541206955367215e+02
-sb7  = -2.24409524465858183362e+01
-
-def erf4(x):
-    '''erf(x) for x in [1/.35,6]'''
-    x0=x
-    x = fabs(x)
-    s = one/(x*x)
-    R=rb0+s*(rb1+s*(rb2+s*(rb3+s*(rb4+s*(rb5+s*rb6)))))
-    S=one+s*(sb1+s*(sb2+s*(sb3+s*(sb4+s*(sb5+s*(sb6+s*sb7))))))
-    z  = ldexp(x0,0)
-    r  =  exp(-z*z-0.5625)*exp((z-x)*(z+x)+R/S)
-    if(z>=0):
-        return one-r/x
-    else:
-        return  r/x-one;
-
-def erfc4(x):
-    '''erfc(x) for x in [2.857142,6]'''
-    return one-erf4(x)
-
-def erf5(x):
-    '''erf(x) for |x| in [6,inf)'''
-    if x>0:
-        return one-tiny
-    return tiny-one
-
-def erfc5(x):
-    '''erfc(x) for |x| in [6,inf)'''
-    if (x>0):
-        return tiny*tiny
-    return two-tiny
-
-#############
-##inf = float('inf')
-##nan = float('nan')
-###########
-inf = float(9e999)
-
-def Erf(x):
-    '''return the error function of x'''
-    f = float(x)
-    if (f == inf):
-        return 1.0
-    elif (f == -inf):
-        return -1.0
-##    elif (f is nan):
-##        return nan
-    else:
-        if (abs(x)<0.84375):
-            return erf1(x)
-        elif (0.84375<=abs(x)<1.25):
-            return erf2(x)
-        elif (1.25<=abs(x)<2.857142):
-            return erf3(x)
-        elif (2.857142<=abs(x)<6):
-            return erf4(x)
-        elif (abs(x)>=6):
-            return erf5(x)
-    
-def Erfc(x):
-    '''return the complementary of error function of x'''
-    f = float(x)
-    if (f == inf):
-        return 0.0
-    elif (f is -inf):
-        return 2.0
-##    elif (f == nan):
-##        return nan
-    else:
-        if (abs(x)<0.84375):
-            return erfc1(x)
-        elif (0.84375<=abs(x)<1.25):
-            return erfc2(x)
-        elif (1.25<=abs(x)<2.857142):
-            return erfc3(x)
-        elif (2.857142<=abs(x)<6):
-            return erfc4(x)
-        elif (abs(x)>=6):
-            return erfc5(x)