Example #1
0
    def __call__ ( self , *x ) :

        n = self.__N 
        assert len ( x ) == n , 'Invalid  argument size'

        xve = [ VE(i)        for i in  x   ] ## force everything to be VE 
        xv  = [    i.value() for i in  xve ] ## get only the values
        
        xv  = tuple ( xv ) 
        
        ## value of the function 
        value = self.__func ( *xv )
        
        ## calculate the covariance 
        cov2  = 0
        for i in range ( n ) :

            c2 = xve[i].cov2()
            if c2 <= 0 or iszero ( c2 ) : continue

            ## calculate the gradient 
            df = self.partial[i] ( *xv ) 
            if iszero ( df )            : continue 
            
            cov2 += c2 * df**2 

        return VE ( value , cov2 ) 
Example #2
0
    def __call__ ( self , args , cor = None ) :
        """Calcualte the value of the scalar function of N arguments
        with uncertainties and correlations 
        
        >>> fun2   = lambda x , y : ...
        >>> fun2e  = EvalNVEcor ( fun2 , 2 )
        >>> cor    = ... # 2x2 symmetric correlation matrix
        >>> x      = ...
        >>> y      = ...    
        >>> result = fun2e ( (x,y) , cor ) ##           
        """
        n = self.N 
        assert len ( args ) == n , 'Invalid argument size'

        ## get value of the function 
        val = self.func ( *args )
        
        c2  = 0
        
        x   = n * [ 0 ]  ## argument 
        g   = n * [ 0 ]  ## gradient 
        
        for i in range ( n ) :

            xi    = VE ( args[i] )
            x [i] = x 
            
            ci    = xi.cov2()
            if ci < 0  or iszero ( ci ) : continue
            
            di    = self.partial[i] ( *args )
            if iszero ( di )            : continue
            
            ei    = xi.error() 

            g [i] = di  
            e [i] = ei
            
            ## diagonal correlation coefficients are assumed to be 1 and ignored! 
            c2   += ci * di * di
            
            for j in range ( i ) : 

                xj   = x  [ j ]
                cj   = xj.cov2 () 
                if cj < 0  or iszero ( cj ) : continue
                dj   = d  [ j ]
                if iszero ( dj )            : continue                
                ej   = e  [ j ]

                rij  =  self.__corr ( cor , i , j ) if cor else 0 
                assert -1 <= rij <= 1 or isequal ( abs ( rij ) , 1 ) ,\
                       'Invalid correlaation coefficient (%d,%d)=%s ' % ( i , j , rij )
                
                c2  += 2.0 * di * dj * rij * ei * ej 
                
        return VE ( val , c2 ) 
Example #3
0
def fmt_pretty_float(value, width=8, precision=6):
    """Format for nice printout of the floating number
    - return format for nice string and the separate exponent 
    >>> fmt , n = fmt_pretty_float ( number ) 
    """
    from ostap.core.ostap_types import integer_types, num_types

    assert isinstance ( value     , num_types     ),\
           'Invalid value parameter %s/%s'   % ( value , type ( value ) )

    ## not finite?
    from ostap.math.base import isfinite
    if not isfinite(value): return "%s", 0

    assert isinstance ( width     , integer_types ) and \
           isinstance ( precision , integer_types ) and 2 <= precision < width, \
           "Invalid width/precision parameters %s/%s" % ( width , precision )

    v = value
    av = abs(v)
    if 100 <= av < 1000:
        fmt2 = '%%+%d.%df' % (width, precision - 2)
        return fmt2, 0
    elif 10 <= av < 100:
        fmt1 = '%%+%d.%df' % (width, precision - 1)
        return fmt1, 0
    elif 1 <= av < 10:
        fmt0 = '%%+%d.%df' % (width, precision)
        return fmt0, 0
    elif 0.1 <= av < 1:
        fmt0 = '%%+%d.%df' % (width, precision)
        return fmt0, 0

    from ostap.math.base import frexp10, iszero
    if iszero(av):
        fmt0 = '%%+%d.%df' % (width, precision)
        return fmt0, 0

    v_a, v_e = frexp10(v)
    if 0 == v_e and iszero(v_a):
        fmt0 = '%%+0%d.%df' % (width, precision)
        return fmt0, 0

    v_a *= 10
    v_e -= 1

    n, r = divmod(v_e, 3)

    ra = v_a * (10**r)

    fmt, p = fmt_pretty_float(ra, width, precision)

    return fmt, p + 3 * n
Example #4
0
    def optimal_step(self, fun, x, h, hmax=-1, args=(), kwargs={}):
        """Get the optimal step (and f(x)) for numerical differentiation
        
        >>> deLevie = ...
        >>> hopt , f0 = deLevier.optimal_step ( fun , x = 0 , h = 0.1 )
        
        """

        ## adjust inital step size
        h = self.adjust_step(x, h, hmax)

        ## get the function value at the given point
        f0 = fun(x, *args, **kwargs)

        dx = delta(x)

        xph = x + h
        h = xph - x

        h_max = hmax if dx < hmax else self.max_step

        ## adjust h
        if 0 < h_max < abs(h):
            h = math.copysign(h_max, h)

        i = self.__I
        j = self.__J

        ## if the intial step is too small, choose another one
        eps_j = self.table2[3]

        if abs(h) < eps_j or abs(h) < dx:
            if iszero(x): h = self.deltas[i]
            else: h = (1 + abs(x)) * eps_j  ## Sect. 7

        ## 1) find the estimate for first and "J"th the derivative with the given step
        d1, dJ = self.derivatives(True, fun, x, h, args=args, kwargs=kwargs)

        ## find the optimal step
        if iszero(dJ) or (iszero(f0) and iszero(x * d1)):

            if iszero(x): hopt = self.deltas[i]
            else: hopt = (1 + abs(x)) * eps_j  ## Sect. 7

        else:

            d_j = self.table2[2]
            hopt = d_j * ((abs(f0) + abs(x * d1)) / abs(dJ))**(1.0 / j)

        ## final adjustment
        hopt = self.adjust_step(x, hopt, hmax)

        return hopt, f0
Example #5
0
    def __init__(
            self,
            name,
            x,  ## the first  dimension  
            y,  ## the second dimension
            n=2,  ## polynomial degree in X and Y
            tau=None):  ## the exponent

        if x.getMin() != y.getMin():
            logger.warning(
                'PSPos2Dsym: x&y have different low  edges %s vs %s' %
                (x.getMin(), y.getMin()))

        if x.getMax() != y.getMax():
            logger.warning(
                'PSPos2Dsym: x&y have different high edges %s vs %s' %
                (x.getMax(), y.getMax()))

        PDF2.__init__(self, name, x, y)

        #
        ## get tau
        #
        taumax = 100
        mn, mx = x.minmax()
        mc = 0.5 * (mn + mx)
        #
        if not iszero(mn): taumax = 100.0 / abs(mn)
        if not iszero(mc): taumax = min(taumax, 100.0 / abs(mc))
        if not iszero(mx): taumax = min(taumax, 100.0 / abs(mx))

        #
        ## the exponential slopes
        #
        self.tau = makeVar(tau, "tau_%s" % name, "tau(%s)" % name, tau, 0,
                           -taumax, taumax)
        #
        self.m1 = x  ## ditto
        self.m2 = y  ## ditto

        #
        num = (n + 1) * (n + 2) / 2 - 1
        self.makePhis(num)
        #

        #
        ## finally build PDF
        #
        self.pdf = Ostap.Models.Expo2DPolSym('exp2Ds_%s' % name,
                                             'Expo2DPolSym(%s)' % name, self.x,
                                             self.y, self.tau, n,
                                             self.phi_list)
Example #6
0
    def __init__(
            self,
            name,  ## the name 
            mass,  ## the variable
            alpha=None,  ## the slope of the first exponent 
            delta=None,  ## (alpha+delta) is the slope of the first exponent
            x0=0,  ## f(x)=0 for x<x0 
            power=0,  ## degree of polynomial
            tau=None):  ##
        #
        PDF.__init__(self, name)
        #
        self.mass = mass
        self.power = power
        #
        mn, mx = mass.minmax()
        mc = 0.5 * (mn + mx)
        taumax = 100
        #
        if not iszero(mn): taumax = 100.0 / abs(mn)
        if not iszero(mc): taumax = min(taumax, 100.0 / abs(mc))
        if not iszero(mx): taumax = min(taumax, 100.0 / abs(mx))
        #
        ## the exponential slope
        #
        self.alpha = makeVar(alpha, "alpha_%s" % name, "#alpha(%s)" % name,
                             alpha, 1, 0, taumax)

        self.delta = makeVar(delta, "delta_%s" % name, "#delta(%s)" % name,
                             delta, 1, 0, taumax)

        self.x0 = makeVar(x0, "x0_%s" % name, "x_{0}(%s)" % name, x0, mn,
                          mn - 0.5 * (mx - mn), mx + 0.5 * (mx - mn))
        #
        #
        if 0 >= self.power:

            self.phis = []
            self.phi_list = ROOT.RooArgList()
            self.pdf = ROOT.RooExponential('exp_%s' % name, 'exp(%s)' % name,
                                           mass, self.tau)

        else:

            #
            self.makePhis(power)
            #

            self.pdf = Ostap.Models.TwoExpoPositive(
                '2expopos_%s' % name, '2expopos(%s)' % name, mass,
                self.alpha, self.delta, self.x0, self.phi_list, mass.getMin(),
                mass.getMax())
Example #7
0
def derivative(fun, x, h=0, I=2, err=False):
    """Calculate the first derivative for the function
    #  @code
    #  >>> fun =  lambda x : x*x
    #  >>> print derivative ( fun , x = 1 ) 
    - see R. De Levie, ``An improved numerical approximation for the first derivative''
    - see https://link.springer.com/article/10.1007/s12039-009-0111-y
    - see http://www.ias.ac.in/chemsci/Pdf-Sep2009/935.pdf
    """

    func = lambda x: float(fun(x))

    ## get the function value at the given point
    f0 = func(x)

    ## adjust the rule
    I = min(max(I, 1), 8)
    J = 2 * I + 1

    _dfun_ = _funcs_[I]
    delta = _delta_(x)

    ## if the intial step is too small, choose another one
    if abs(h) < _numbers_[I][3] or abs(h) < delta:
        if iszero(x): h = _numbers_[0][I]
        else: h = abs(x) * _numbers_[I][3]

    h = max(h, 2 * delta)

    ## 1) find the estimate for first and "J"th the derivative with the given step
    d1, dJ = _dfun_(func, x, h, True)

    ## find the optimal step
    if iszero(dJ) or (iszero(f0) and iszero(x * d1)):
        if iszero(x): hopt = _numbers_[0][I]
        else: hopt = abs(x) * _numbers_[I][3]
    else:
        hopt = _numbers_[I][2] * ((abs(f0) + abs(x * d1)) / abs(dJ))**(1.0 / J)

    ## finally get the derivative
    if not err: return _dfun_(func, x, hopt, False)

    ## estimate the uncertainty, if needed
    d1, dJ = _dfun_(func, x, hopt, True)

    e = _numbers_[I][1] / _numbers_[I][2] * J / (J - 1)
    e2 = e * e * (J * _eps_ + abs(f0) +
                  abs(x * d1))**(2 - 2. / J) * abs(dJ)**(2. / J)
    return VE(d1, 4 * e2)
Example #8
0
def _ve_b2s_(s):
    """Get background-over-signal ratio B/S estimate from the equation:
    error(S) = 1/sqrt(S) * sqrt ( 1 + B/S).
    >>> v = ...
    >>> b2s = v.b2s() ## get B/S estimate
    """
    #
    vv = s.value()
    if vv <= 0 or iszero(vv): return VE(-1, 0)
    #
    c2 = s.cov2()
    if c2 <= 0 or iszero(c2): return VE(-1, 0)
    elif isequal(vv, c2): return VE(1, 0)
    elif c2 < vv: return VE(-1, 0)
    #
    return c2 / s - 1.0
Example #9
0
 def _solve_(func, fval, xmn, xmx, *args):
     ##
     if isequal(xmn, xmx): return xmn
     ##
     ifun = lambda x, *a: func(x, *a) - fval
     ##
     fmn = ifun(xmn)
     if iszero(ifun(xmn)): return xmn
     fmx = ifun(xmx)
     if iszero(ifun(xmx)): return xmx
     ##
     if 0 < fmx * fmn:  ## more or less arbitrary choice
         return xmx if abs(fmx) <= abs(fmn) else xmn
     #
     from ostap.math.rootfinder import findroot
     return findroot(ifun, xmn, xmx, args=args)
Example #10
0
 def __call__(self, x, *args):
     """Evaluate the function taking into account uncertainty in the argument        
     >>> import math 
     >>> x    = VE(1,0.1**2)
     >>> sin1 = EvalVE( math.sin , lambda s : math.cos(s) )
     >>> print 'sin1(x) = %s ' % sin1(x) 
     >>> sin2 = EvalVE( math.sin )
     >>> print 'sin2(x) = %s ' % sin2(x)
     """
     #
     ## evaluate the function
     val = self._value_(x, *args)
     #
     ## no uncertainties?
     if isinstance(x, (float, int, long)):
         return VE(val, 0)
         # ignore small or invalid uncertanties
     elif 0 >= x.cov2() or iszero(x.cov2()):
         return VE(val, 0)
     # evaluate the derivative
     d = self._deriv(float(x), *args)
     ## calculate the variance
     cov2 = d * d * x.cov2()
     ## get a final result
     return VE(val, cov2)
Example #11
0
    def __init__(
            self,
            name,  ## the name 
            mass,  ## the variable
            power=0,  ## degree of polynomial
            tau=None,  ## exponential slope 
            the_phis=None):  ## the phis...
        #
        PDF.__init__(self, name)
        #
        self.mass = mass
        self.power = power
        #
        mn, mx = mass.minmax()
        mc = 0.5 * (mn + mx)
        taumax = 100
        #
        if not iszero(mn): taumax = 100.0 / abs(mn)
        if not iszero(mc): taumax = min(taumax, 100.0 / abs(mc))
        if not iszero(mx): taumax = min(taumax, 100.0 / abs(mx))
        #
        ## the exponential slope
        #
        self.tau = makeVar(tau, "tau_%s" % name, "tau(%s)" % name, tau, 0,
                           -taumax, taumax)
        #
        if the_phis:
            ## copy phis
            self.makePhis(power, the_phis=the_phis)  ## copy phis

        elif 0 >= self.power:

            self.phis = []
            self.phi_list = ROOT.RooArgList()
            self.pdf = ROOT.RooExponential('exp_%s' % name, 'exp(%s)' % name,
                                           mass, self.tau)

        else:

            #
            self.makePhis(power)
            #

        self.pdf = Ostap.Models.ExpoPositive('expopos_%s' % name,
                                             'expopos(%s)' % name, mass,
                                             self.tau, self.phi_list,
                                             mass.getMin(), mass.getMax())
Example #12
0
 def _solve_  ( func , fval , xmn , xmx , *args ) :
     ##
     if isequal (  xmn , xmx   )  : return xmn
     ## 
     ifun = lambda x,*a : func(x,*a) - fval
     ## 
     fmn = ifun  ( xmn )
     if iszero  ( ifun ( xmn ) )  : return xmn
     fmx = ifun  ( xmx )
     if iszero  ( ifun ( xmx ) )  : return xmx 
     ##
     if 0 < fmx * fmn : ## more or less arbitrary choice 
         return xmx if abs ( fmx ) <= abs ( fmn ) else xmn 
     #
     ## use scipy to find solution 
     from scipy import optimize
     return optimize.brentq (  ifun , xmn , xmx , args = args )
Example #13
0
def derivative(fun, x, h=0, I=2, err=False):
    """Calculate the first derivative for the function
    #  @code
    #  >>> fun =  lambda x : x*x
    #  >>> print derivative ( fun , x = 1 ) 
    """

    func = lambda x: float(fun(x))

    ## get the function value at the given point
    f0 = func(x)

    ## adjust the rule
    I = min(max(I, 1), 8)
    J = 2 * I + 1

    _dfun_ = _funcs_[I]
    delta = _delta_(x)

    ## if the intial step is too small, choose another one
    if abs(h) < _numbers_[I][3] or abs(h) < delta:
        if iszero(x): h = _numbers_[0][I]
        else: h = abs(x) * _numbers_[I][3]

    h = max(h, 2 * delta)

    ## 1) find the estimate for first and "J"th the derivative with the given step
    d1, dJ = _dfun_(func, x, h, True)

    ## find the optimal step
    if iszero(dJ) or (iszero(f0) and iszero(x * d1)):
        if iszero(x): hopt = _numbers_[0][I]
        else: hopt = abs(x) * _numbers_[I][3]
    else:
        hopt = _numbers_[I][2] * ((abs(f0) + abs(x * d1)) / abs(dJ))**(1.0 / J)

    ## finally get the derivative
    if not err: return _dfun_(func, x, hopt, False)

    ## estimate the uncertainty, if needed
    d1, dJ = _dfun_(func, x, hopt, True)

    e = _numbers_[I][1] / _numbers_[I][2] * J / (J - 1)
    e2 = e * e * (J * _eps_ + abs(f0) +
                  abs(x * d1))**(2 - 2. / J) * abs(dJ)**(2. / J)
    return VE(d1, 4 * e2)
Example #14
0
    def __call__ ( self , x , y , cxy = 0 ) :
        """Evaluate the function 
        >>> func2 = lambda x,y : x*x + y*y
        >>> eval2 = Eval2VE ( func2 )
        >>> x = VE(1,0.1**2)
        >>> y = VE(2,0.1**2)
        >>> print eval2(x,y)    ## treat x,y as uncorrelated 
        >>> print eval2(x,y, 0) ## ditto 
        >>> print eval2(x,y,+1) ## treat x,y as 100% correlated 
        >>> print eval2(x,y,-1) ## treat x,y as 100% anti-correlated
        """
        assert isinstance ( cxy , num_types ) and \
               ( abs ( cxy ) <= 1 or isequal ( abs ( cxy ) , 1 ) ) , \
               'Invalid correlation coefficient %s' % cxy 
        
        x   = VE ( x ) 
        y   = VE ( y )
        
        xv  = x.value()
        yv  = y.value()
        
        val = self.func ( xv , yv )

        xc2 = x.cov2()
        yc2 = x.cov2()
        
        x_plain = xc2 <= 0 or iszero ( xc2 )
        y_plain = yc2 <= 0 or iszero ( yc2 )
        
        #
        if x_plain and y_plain : return VE ( val , 0 )
        
        #
        ## here we need to calculate the uncertainties
        # 
        dx   = self.partial[0] ( xv , yv ) if not x_plain else 0 
        dy   = self.partial[1] ( xv , yv ) if not y_plain else 0 
        #
        
        cov2 = dx * dx * xc2 + dy * dy * yc2
        
        if cxy and xc2 and yc2 :
            cov2 += 2 * cxy * dx * dy * math.sqrt ( xc2 * yc2 ) 
            
        return VE ( val , cov2 )
Example #15
0
        def iifun(f):

            if iszero(f): x1, x2 = xmin, xmax
            elif isequal(f, fm): return -yval
            else:
                x1 = _solve_(func, f, xmin, xmode)
                x2 = _solve_(func, f, xmode, xmax)

            return _integral_(func, x1, x2) - yval
Example #16
0
    def __init__(
            self,
            name,
            x,  ##  the first  dimension  
            y,  ##  the second dimension
            psy=None,  ##  phase space in Y, Ostap::Math::PhaseSpaceNL 
            nx=2,  ##  polynomial degree in X 
            ny=2,  ##  polynomial degree in Y 
            tau=None):  ##  the exponent

        PDF2.__init__(self, name, x, y)

        #
        ## get tau
        taumax = 100
        mn, mx = x.minmax()
        mc = 0.5 * (mn + mx)
        #
        if not iszero(mn): taumax = 100.0 / abs(mn)
        if not iszero(mc): taumax = min(taumax, 100.0 / abs(mc))
        if not iszero(mx): taumax = min(taumax, 100.0 / abs(mx))

        #
        ## the exponential slope
        #
        self.tau = makeVar(tau, "tau_%s" % name, "tau(%s)" % name, tau, 0,
                           -taumax, taumax)
        #

        self.psy = psy

        #
        num = (nx + 1) * (ny + 1) - 1
        self.makePhis(num)
        #

        #
        ## finally build PDF
        #
        self.pdf = Ostap.Models.ExpoPS2DPol('ps2D_%s' % name,
                                            'PS2DPol(%s)' % name, self.x,
                                            self.y, self.tau, self.psy, nx, ny,
                                            self.phi_list)
Example #17
0
def _laguerre_ ( x , f , d1 = None , d2 = None ) :
    """ Root finding for Bernstein polnomials using Laguerre's method
    - https://en.wikipedia.org/wiki/Laguerre%27s_method
    """
    fn   = f.norm() / 10 
    n    = f.degree()
    
    xmin = f.xmin ()
    xmax = f.xmax ()
    
    l    = xmax - xmin
    
    if not d1 : d1 =  f.derivative()
    if not d2 : d2 = d1.derivative()
    
    if  not f.xmin() <= x <= f.xmax() :
        x = 0.5 * ( xmin + xmax ) 

    if 1 ==  f.degree() :
        
        p0 = f [ 0 ]
        p1 = f [ 1 ]
        
        s0 = signum ( p0 )
        s1 = signum ( p1 )
        
        return ( p1 * xmin - p0 * xmax ) / ( p1 - p0) , 
        

    ## the convergency is cubic, therefore 16 is *very* larger number of iterations 
    for i in  range(16) : 
        
        if  not xmin <= x <= xmax :
            ## something goes wrong: multiple root? go to derivative
            break 

        vx = f.evaluate(x)
        if iszero ( vx ) or isequal ( fn +  vx , fn ) : return x,
        
        G =         d1 ( x ) / vx
        H = G * G - d2 ( x ) / vx
        
        d = math.sqrt ( ( n - 1 ) * ( n * H - G * G ) )
        if G < 0 : d = -d

        a = n / ( G + d ) 

        x -= a

        if isequal ( a + x , x ) : return x,  
        
    ## look for derivative
    r =  _laguerre_ ( x , d1 , d2 , d2.derivative() )
    if r : r = r[:1] + r
    return r
Example #18
0
    def __call__ ( self , args , cov2 = None ) :
        """Calcualte the value of the scalar function of N (scalar) arguments 
        with the given NxN covariance matrix
        
        >>> fun2   = lambda x , y : ...
        >>> fun2e  = EvalNVEcov ( fun2 , 2 )
        >>> cov2   = ... # 2x2 symmetric covariance matrix
        >>> result = fun2e ( (1,5) , cov2 ) ##   
        
        """
        
        n = self.N 
        assert len ( args ) == n , 'Invalid argument size'

        ## get value of the function 
        val = float ( self.func ( *args ) ) 
        
        ## no covariance matrix is specified ?
        if not cov2 : return val
        
        c2 = 0
        g  = n * [ 0 ] ## gradient 
        
        for i in range ( n ) :

            di    = self.partial[i] ( *args )
            if iszero ( di ) : continue
            
            g [i] = di  

            cii   = self.__cov2 ( cov2 , i , i )
            c2   += di * di * cii
            
            for j in range ( i ) : 

                dj   = g [ j ]
                if iszero ( dj ) : continue
                
                cij  =     self.__cov2 ( cov2 , i , j ) 
                c2  += 2 * di * dj * cij 

        return VE ( val , c2 ) 
Example #19
0
def _ve_purity_(s):
    """Calculate the ``effective purity'' ratio using the identity
    p = S/(S+B) = 1/( 1 + B/S ), 
    - and the effective ``background-to-signal'' ratio B/S is estimated as
    B/S = sigma^2(S)/S - 1
    - Finally one gets
    p = S / sigma^2(S) 
    - see Ostap::Math::b2s 
    - see Ostap::Math::purity
    """
    #
    vv = s.value()
    if vv <= 0 or iszero(vv): return VE(-1, 0)
    #
    c2 = s.cov2()
    if c2 <= 0 or iszero(c2): return VE(-1, 0)
    elif isequal(vv, c2): return VE(1, 0)
    elif c2 < vv: return VE(-1, 0)
    #
    return s / cov2
Example #20
0
    def __call__(self, x, y, cxy=0):
        """Evaluate the function 
        >>> func2 = lambda x,y : x*x + y*y
        >>> eval2 = Eval2VE ( func2 )
        >>> x = VE(1,0.1**2)
        >>> y = VE(2,0.1**2)
        >>> print eval2(x,y)    ## treat x,y as uncorrelated 
        >>> print eval2(x,y, 0) ## ditto 
        >>> print eval2(x,y,+1) ## treat x,y as 100% correlated 
        >>> print eval2(x,y,-1) ## treat x,y as 100% anti-correlated
        """
        ## evaluate the function
        val = self._value_(x, y)
        #
        x = VE(x)
        y = VE(y)
        #
        x_plain = x.cov2() <= 0 or iszero(x.cov2())
        y_plain = y.cov2() <= 0 or iszero(y.cov2())
        #
        if x_plain and y_plain: return VE(val, 0)
        #
        ## here we need to calculate the uncertainties
        #
        cov2 = 0.0
        #
        fx = self.dFdX(x, y.value()) if not x_plain else 0
        fy = self.dFdY(x.value(), y) if not y_plain else 0
        #
        if not x_plain: cov2 += fx * fx * x.cov2()
        if not y_plain: cov2 += fy * fy * y.cov2()
        #
        if not x_plain and not y_plain:
            ## adjust the correlation coefficient:
            cxy = min(max(-1, cxy), 1)
            if not iszero(cxy):
                cov2 += 2 * cxy * fx * fy * x.error() * y.error()

        return VE(val, cov2)
Example #21
0
    def __init__(
            self,
            name,
            x,  ##  the first  dimension  
            y,  ##  the second dimension
            nx=2,  ##  polynomial degree in X 
            ny=2,  ##  polynomial degree in Y
            taux=None,  ##  the exponent in X 
            tauy=None):  ##  the exponent in Y

        PDF2.__init__(self, name, x, y)

        #
        ## get tau_x
        #
        xtaumax = 100
        mn, mx = x.minmax()
        mc = 0.5 * (mn + mx)
        #
        if not iszero(mn): xtaumax = 100.0 / abs(mn)
        if not iszero(mc): xtaumax = min(xtaumax, 100.0 / abs(mc))
        if not iszero(mx): xtaumax = min(xtaumax, 100.0 / abs(mx))

        ytaumax = 100
        mn, mx = y.minmax()
        mc = 0.5 * (mn + mx)
        #
        if not iszero(mn): ytaumax = 100.0 / abs(mn)
        if not iszero(mc): ytaumax = min(ytaumax, 100.0 / abs(mc))
        if not iszero(mx): ytaumax = min(ytaumax, 100.0 / abs(mx))

        #
        ## the exponential slopes
        #
        self.taux = makeVar(taux, "taux_%s" % name, "taux(%s)" % name, taux, 0,
                            -xtaumax, xtaumax)
        #
        self.tauy = makeVar(tauy, "tauy_%s" % name, "tauy(%s)" % name, tauy, 0,
                            -ytaumax, ytaumax)
        #

        self.m1 = x  ## ditto
        self.m2 = y  ## ditto

        #
        num = (nx + 1) * (ny + 1) - 1
        self.makePhis(num)
        #

        #
        ## finally build PDF
        #
        self.pdf = Ostap.Models.Expo2DPol('exp2D_%s' % name,
                                          'Expo2DPol(%s)' % name, self.x,
                                          self.y, self.taux, self.tauy, nx, ny,
                                          self.phi_list)
Example #22
0
File: ve.py Project: mazurov/ostap
def _ve_gauss_(s, accept=lambda a: True, nmax=1000):
    """ Get the gaussian random number
    >>> v = ...  ## the number with error
    ## get 100 random numbers 
    >>> for i in range ( 0, 100 ) : print v.gauss()    
    ## get only non-negative numbers 
    >>> for j in range ( 0, 100 ) : print v.gauss( lambda s : s > 0 )
    """
    #
    if 0 >= s.cov2() or iszero(s.cov2()): return s.value()  ## return
    #
    v = s.value()
    e = s.error()
    #
    for i in xrange(nmax):
        r = _gauss(v, e)
        if accept(r): return r

    logger.warning("Can'n generate proper random number %s" % s)
    return v
Example #23
0
    def __call__ ( self , s ) :
        """   Calculate the weigth for the given ``event'' (==record in TTree/TChain or RooDataSet):
        >>> weight = Weight ( ... )
        >>> tree   = ...
        >>> w = weight ( tree )
        """

        ## initialize the weight 
        weight  = VE(1,0) 

        ## loop over functions 
        for i in self.__vars :
            
            funval    = i[1] ## accessor 
            functions = i[2] ## the functions 

            ##  get the weight arguments for given event 
            v       = funval ( s )

            ww = VE(1.0)
            
            for f in functions :

                if isinstance ( v , tuple ) : w = f ( *v )
                else                        : w = f (  v )

                ww *= w # update the weight factor 

            ## keep the statistics
            cnt  = i[3]
            cnt += ww.value()

            ## update the global weight 
            weight *= ww
            
        vw = weight.value()
        
        self.__counter += vw 
        if iszero ( vw ) : self.__nzeroes += 1
            
        return vw
Example #24
0
def _ms_corr_(self):
    """Get the correlation matrix
    >>> mtrx = ...
    >>> corr = mtrx.correlations()
    """
    from math import sqrt

    _t = type(self)
    _c = _t()
    _rows = self.kRows
    _ok1 = True
    _ok2 = True
    for i in range(0, _rows):

        ii = self(i, i)
        if 0 > ii or iszero(ii):
            _ok1 = False
            _nan = float('nan')
            for j in range(i, _rows):
                _c[i, j] = _nan
            continue

        sii = sqrt(ii)
        _c[i, i] = 1

        for j in range(i + 1, _rows):
            jj = self(j, j)
            sjj = sqrt(jj)
            ij = self(i, j)
            eij = ij / (sii * sjj)
            if 1 < abs(eij): _ok2 = False
            _c[i, j] = eij

    if not _ok1:
        logger.error("correlations: zero or negative diagonal element")
    if not _ok2: logger.error("correlations: invalid non-diagonal element")

    return _c
Example #25
0
def makeWeights(
        dataset,
        plots=[],
        database="weights.db",
        compare=None,  ## comparison function 
        delta=0.001,  ## delta for ``mean''  weight variation
        minmax=0.05,  ## delta for ``minmax'' weight variation
        power=0,  ## auto-determination
        debug=True,  ## save intermediate information in DB
        tag="Reweighting"):

    assert 0 < delta, "makeWeights(%s): Invalid value for ``delta''  %s" % (
        tag, delta)
    assert 0 < minmax, "makeWeights(%s): Invalid value for ``minmax'' %s" % (
        tag, minmax)

    from ostap.logger.colorized import allright, attention, infostr
    from ostap.utils.basic import isatty

    power = power if power >= 1 else len(plots)

    nplots = len(plots)
    if 1 < nplots:
        import math
        fudge_factor = math.sqrt(1.0 / max(2.0, nplots - 1.0))
        delta = delta * fudge_factor
        minmax = minmax * fudge_factor

    save_to_db = []
    ## number of active plots for reweighting
    for wplot in plots:

        what = wplot.what  ## variable/function to plot/compare
        how = wplot.how  ## weight and/or additional cuts
        address = wplot.address  ## address in database
        hdata0 = wplot.data  ## original "DATA" object
        hmc0 = wplot.mc_histo  ## original "MC"   histogram
        ww = wplot.w  ## relative weight
        #
        # normailze the data
        #
        hdata = hdata0
        if isinstance(hdata, ROOT.TH1): hdata = hdata.density()

        # =====================================================================
        ## make a plot on (MC) data with the weight
        # =====================================================================
        dataset.project(hmc0, what, how)

        st = hmc0.stat()
        mnmx = st.minmax()
        if iszero(mnmx[0]):
            logger.warning("Reweighting: statistic goes to zero %s/``%s''" %
                           (st, address))

        # =====================================================================
        ## normalize MC
        # =====================================================================
        hmc = hmc0.density()

        # =====================================================================
        ## calculate  the reweighting factor : a bit conservative (?)
        #  this is the only important line
        # =====================================================================

        #  try to exploit finer binning if/when possible
        if   isinstance ( hmc   , ( ROOT.TH1F , ROOT.TH1D ) ) and \
           isinstance ( hdata , ( ROOT.TH1F , ROOT.TH1D ) )   and \
           len ( hmc ) >= len( hdata )                        :
            w = (1.0 / hmc) * hdata  ## NB!
            ## elif isinstance ( hmc   , ( ROOT.TH2F , ROOT.TH2D ) ) and \
            ##    isinstance ( hdata , ( ROOT.TH2F , ROOT.TH2D ) )   and \
            ##    len ( hmc.GetXaxis() ) >= len( hdata.GetXaxis () ) and \
            ##    len ( hmc.GetYaxis() ) >= len( hdata.GetYaxis () ) : w = ( 1.0 / hmc ) * hdata ## NB!
            ## elif isinstance ( hmc   , ( ROOT.TH3F , ROOT.TH3D ) ) and \
            ##    isinstance ( hdata , ( ROOT.TH3F , ROOT.TH3D ) )   and \
            ##    len ( hmc.GetXaxis() ) >= len( hdata.GetXaxis () ) and \
            ##    len ( hmc.GetYaxis() ) >= len( hdata.GetYaxis () ) and \
            ##    len ( hmc.GetZaxis() ) >= len( hdata.GetZaxis () ) : w = ( 1.0 / hmc ) * hdata ## NB!
        else:
            w = hdata / hmc  ## NB!

        # =====================================================================
        ## scale & get the statistics of weights
        w /= w.stat().mean().value()
        cnt = w.stat()
        #
        mnw, mxw = cnt.minmax()
        wvar = cnt.rms() / cnt.mean()
        good1 = wvar.value() <= delta
        good2 = abs(mxw - mnw) <= minmax
        good = good1 and good2  ## small variance?
        #
        afunc1 = allright if good1 else attention
        afunc2 = allright if good2 else attention
        #
        message = "%s: %24s:" % (tag, address)
        message += ' ' + 'mean=%12s' % cnt.mean().toString('(%4.2f+-%4.2f)')
        message += ' ' + afunc2('min/max=%-5.3f/%5.3f' %
                                (cnt.minmax()[0], cnt.minmax()[1]))
        message += ' ' + afunc1('rms=%s[%%]' %
                                (wvar * 100).toString('(%4.2f+-%4.2f)'))
        logger.info(message)
        #
        ## make decision based on the variance of weights
        #
        mnw, mxw = cnt.minmax()
        if good:  ## small variance?
            message = "%s: No more reweights for %s" % (tag, address)
            message += ' ' + allright("min/max/rms=%+3.1f/%+3.1f/%3.1f[%%]" %
                                      ((mnw - 1) * 100,
                                       (mxw - 1) * 100, 100 * wvar))
            logger.info(message)
            del w, hdata, hmc
        else:
            save_to_db.append((address, ww, hdata0, hmc0, hdata, hmc, w))
        # =====================================================================
        ## make a comparison (if needed)
        # =====================================================================
        if compare: compare(hdata0, hmc0, address)

    ## for single reweighting
    ## if 1 == nplots : power = 1

    ## if power != nplots :
    #    logger.info ( "%s: ``power'' is %g/#%d"  % ( tag , power , nplots  ) )

    active = [p[0] for p in save_to_db]
    all = [p.address for p in plots]
    for i, a in enumerate(all):
        if a in active:
            if isatty(): all[i] = attention(a)
            else: all[i] = '*' + a + '*'
        else:
            if isatty(): all[i] = allright(a)

    logger.info("%s: reweights are: %s" % (tag, (', '.join(all))))

    ## if len ( active ) != nplots :
    ##    if database and save_to_db :
    ##        power += ( nplots - len ( active ) )
    ##        logger.info  ("%s: ``power'' is changed to %g" %  ( tag , power ) )

    nactive = len(active)
    while database and save_to_db:

        entry = save_to_db.pop()

        address, ww, hd0, hm0, hd, hm, weight = entry

        ## eff_exp = 1.0  / power
        ## eff_exp = 0.95 / ( 1.0 * nactive ) ** 0.5

        cnt = weight.stat()
        mnw, mxw = cnt.minmax()

        if 0.95 < mnw and mxw < 1.05:
            eff_exp = 0.75 if 1 < nactive else 1.50
        elif 0.90 < mnw and mxw < 1.10:
            eff_exp = 0.70 if 1 < nactive else 1.30
        elif 0.80 < mnw and mxw < 1.20:
            eff_exp = 0.65 if 1 < nactive else 1.25
        elif 0.70 < mnw and mxw < 1.30:
            eff_exp = 0.60 if 1 < nactive else 1.15
        elif 0.50 < mnw and mxw < 1.50:
            eff_exp = 0.55 if 1 < nactive else 1.10
        else:
            eff_exp = 0.50 if 1 < nactive else 1.0

        ## print 'effective exponent is:', eff_exp , address , mnw , mxw , (1.0/mnw)*mnw**eff_exp , (1.0/mxw)*mxw**eff_exp

        if 1 < nactive and 1 != ww:
            eff_exp *= ww
            logger.info("%s: apply ``effective exponent'' of %.3f for ``%s''" %
                        (tag, eff_exp, address))

        if 1 != eff_exp and 0 < eff_exp:
            weight = weight**eff_exp

        ## print 'WEIGHT stat', eff_exp, weight.stat()

        ## hmmmm... needed ? yes!
        #if 1 < power : weight = weight ** ( 1.0 / power )

        ## relative importance
        #if 1 != ww :
        #    logger.info  ("%s: apply ``relative importance factor'' of %.3g for ``'%s'" % ( tag , ww , address ) )
        #    weight = weight ** ww

        with DBASE.open(database) as db:

            db[address] = db.get(address, []) + [weight]

            if debug:
                addr = address + ':REWEIGHTING'
                db[addr] = db.get(addr, []) + list(entry[2:])

        del hd0, hm0, hd, hm, weight, entry

    return active
Example #26
0
def solve (  bp  , C = 0 , split = 2 ) :
    """Solve   equation  B(x) = C, where B(x) is  Bernstein polynomial, and
    C is  e.g.  constant or another polynomial
    >>> bernstein = ...
    >>> roots = bernstein.solve ()
    >>> roots = solve ( bernstein , C = 0 ) ## ditto
    """
    
    ## construct the equation  b'(x)=0:
    bp = bp.bernstein() 
    if C : bp = bp - C
    
    ## 1) zero-degree polynomial
    if   0 == bp.degree() :

        if iszero ( bp[0] ) : return bp.xmin(),
        return () 
    
    ## 2) linear polynomial
    elif 1 == bp.degree() :

        x0 = bp.xmin()
        x1 = bp.xmax()
        
        p0 = bp[0]
        p1 = bp[1]

        s0 = signum ( p0 )
        s1 = signum ( p1 )

        bn = bp.norm() 
        if  iszero ( p0 ) or isequal ( p0 + bn , bn ) : s0 = 0
        if  iszero ( p1 ) or isequal ( p1 + bn , bn ) : s1 = 0
        
        if   s0 ==     0 : return x0,  ## 
        elif s1 ==     0 : return x1,  ##
        elif s0 * s1 > 0 : return ()   ## no roots
        #
        return ( p1 * x0 - p0 * x1 ) / ( p1 - p0) , 

    ## make a copy & scale is needed 
    bp  = _scale_ ( bp + 0 ) 

    ##  norm of polynomial 
    bn = bp.norm()

    ## check number of roots
    nc = bp.sign_changes()
    if not nc : return ()      ## no roots !   RETURN

    ## treat separetely roots at the left and right edges
    roots = []
    while 1 <= bp.degree() and isequal ( bp[0] +  bn , bn ) :
        bp   -= bp[0]
        bp    = bp.deflate_left() 
        bp    = _scale_ ( bp ) 
        bn    = bp.norm ()
        roots.append ( bp.xmin() )        
    if roots : return tuple(roots) + bp.solve ( split = split ) 
    
    roots = []
    while 1 <= bp.degree() and isequal ( bp[-1] +  bn , bn ) :
        bp -= bp[-1]
        bp  = bp.deflate_right() 
        bp  = _scale_ ( bp ) 
        bn  = bp.norm () 
        roots.append ( bp.xmax() )        
    if roots : return bp.solve ( split = split ) + tuple(roots) 

    ## check again number of roots
    nc = bp.sign_changes()
    if not nc : return ()      ## no roots !   RETURN
    
    # =========================================================================
    ## there are  many roots in the interval 
    # =========================================================================


    if 1 < nc :

        xmin = bp.xmin ()
        xmax = bp.xmax ()
        
        lcp  = bp.left_line_hull()
        if ( not lcp is None ) and xmin <= lcp <= xmax : xmin = max ( xmin , lcp )
        
        rcp  = bp.right_line_hull()
        if ( not rcp is None ) and xmin <= rcp <= xmax : xmax = min ( xmax , rcp )

        # =====================================================================
        ## Two strategies for isolation of roots:
        #  - use control polygon 
        #  - use the derivative 
        #  For both cases, the zeros of contol-polygon and/or derivatives
        #  are tested to be the roots of  polynomial..
        #  If they corresponds to the roots, polinomial is properly deflated and
        #  deflated roots are collected
        #  Remaining points are used to (recursively) split interval into smaller
        #  intervals with presumably smaller number of roots 
        
        #
        if 0 < split :

            cps = bp.crossing_points()
            splits = [ xmin ]
            for xp in cps :
                if xmin < xp < xmax : splits.append ( xp )
            splits.append ( xmax ) 

            split -= 1
            
        else :
            
            ## use the roots of derivative 
            dd = bp.derivative()
            rd = dd.solve ( split = split )
            if not rd :
                ## use bisection 
                nrd = xmin, 0.5 * ( xmin + xmax ), xmax
            else :
                ## use roots of derivative 
                nrd = [ xmin , xmax ] 
                for  r in  rd :
                    if xmin < r < xmax :
                        found = False 
                        for  rr in nrd :
                            if isequal ( r , rr ) :
                                found = True
                                break 
                        if not found : nrd.append ( r )
                nrd.sort()                
            splits =  list(nrd)
            
        ## use simple bisection
        if 2 >= len ( splits ) :
            if xmin < xmax : splits =     xmin   , 0.5*(   xmin  +   xmax  ) ,    xmax
            else           : splits =  bp.xmin() , 0.5*(bp.xmin()+bp.xmax()) , bp.xmax()
            splits = list(splits) 
        
        roots = []
        for s in splits :
            
            bv  = bp.evaluate ( s ) 
            bn = bp.norm() 
            while 1 <= bp.degree() and isequal ( bv + bn , bn ) :
                bp -= bv 
                bp  = bp.deflate  ( s  )
                bp  = _scale_     ( bp ) 
                bn  = bp.norm     (    )
                bv  = bp.evaluate ( s  ) 
                roots.append  ( s )
                for q in splits :
                    if  isequal ( q , s ) :
                        splits.remove ( q )
                
        if roots :
            roots += list ( bp.solve ( split =  ( split - 1 ) ) )
            roots.sort()
            return tuple(roots)

        if 2 == len(splits) :
            if isequal ( bp.xmin() , splits[0] ) and isequal ( bp.xmax() , splits[1] ) :
                xmn    = splits[0]
                xmx    = splits[1]
                splits = [ xmn , 0.5*(xmn+xmx) , xmx ] 
                
        ns = len(splits)
        for i in range(1,ns) :
            xl = splits[i-1]
            xr = splits[i  ]            
            bb = _scale_ ( Bernstein ( bp , xl , xr ) )
            roots += bb.solve ( split = ( split - 1 ) )

        roots.sort()
        return  tuple ( roots )   ##  RETURN


    # =========================================================================
    ## there is exactly 1 root here
    # =========================================================================
    
    l0 = ( bp.xmax() -  bp.xmin() ) / ( bp.degree() + 1 )

    ## trivial case 
    if 1 == bp.degree() :        
        y0 =  bp[ 0]
        y1 =  bp[-1]
        x  = ( y1 * bp.xmin() -  y0 * bp.xmax() ) / ( y1 - y0)
        return x,
    
    ## make several iterations (not to much) for better isolation of root
    for i in range ( bp.degree() + 1 ) : 

        xmin = bp.xmin ()
        xmax = bp.xmax ()
        bn   = bp.norm ()

        lcp = bp.left_line_hull  ()
        if not lcp is None :
            if   isequal ( lcp , xmin ) : return  lcp,                      ## RETURN
            elif lcp <= xmax or isequal ( lcp , xmax ) : 
                bv =  bp.evaluate ( lcp )
                if  iszero ( bv ) or isequal ( bv + bn , bn ) : return lcp, ## RETURN
            xmin = max ( xmin , lcp )
                
        rcp = bp.right_line_hull () 
        if not rcp is None :
            if   isequal ( lcp , xmax ) : return  rcp,                      ## RETURN
            elif lcp >= xmin or isequal ( lcp , xmin ) : 
                bv =  bp.evaluate ( rcp )
                if  iszero ( bv ) or isequal ( bv + bn , bn ) : return rcp, ## RETURN
            xmax = min ( xmax , rcp )

        ## 
        if isequal ( xmin , xmax ) : return 0.5*(xmin+xmax),               ## RETURN

        if xmin >= xmax : break                             ## BREAK
        
        ## avoid too iterations - it decreased the precision 
        if 10 * ( xmax - xmin )  < l0  : break              ## BREAK  
        
        s0  =  signum ( bp[ 0] )
        s1  =  signum ( bp[-1] )
        
        smn =  signum ( bp.evaluate ( xmin ) )
        smx =  signum ( bp.evaluate ( xmax ) )

        ##  we have lost the root ?
        if ( s0 * s1 ) * ( smn * smx ) < 0 :  break           ## BREAK 

        ## refine the polynomial: 
        _bp = Bernstein ( bp , xmin , xmax )
        _bp = _scale_ ( _bp )
        _nc = _bp.sign_changes()

        ## we have lost the root 
        if not _nc : break                                   ## BREAK 

        bp = _bp 
        bn = bp.norm()

    # =========================================================================
    ## start the of root-polishing machinery
    # ========================================================================= 

    f = bp 
    d1 = f .derivative ()
    d2 = d1.derivative ()
    
    cps = bp.crossing_points()
    if cps : x = cps[0]
    else   : x = 0.5*(bp.xmin()+bp.xmax()) 

    ##  use Laguerre's method to refine the isolated root 
    l = _laguerre_ ( x , f , d1 , d2 )

    return l 
Example #27
0
def solve(bs, C=0, split=5):
    """Solve equation B(x) = C
    
    bs : (input)  b-spline
    C  : (input) right-hand side
    
    :Example:  
    >>> bs = ...
    >>> print bs.solve() 
    """

    _bs = bs - C

    if 1 >= _bs.degree():
        return _bs.crossing_points(True)

    ## scale if needed
    _bs = _scale_(_bs)

    ## check zeroes of control polygon
    cps = _bs.crossing_points()
    ncp = len(cps)
    bsn = _bs.norm()
    ##
    xmin = _bs.xmin()
    xmax = _bs.xmax()

    for i in range(20):

        if not cps: return ()  ## RETURN

        inserted = False
        for x in cps:
            if isequal(x, _bs.xmin()): continue  ## CONTINUE
            if isequal(x, _bs.xmax()): continue  ## CONTINUE
            bx = _bs(x)
            if iszero(bx) or isequal(bx + bsn, bsn): continue
            if _bs.insert(x): inserted = True

        ## all zeroes are already inserted....
        if not inserted:
            return cps  ## RETURN

        cps = _bs.crossing_points(False)
        if not cps:
            ## roots have disapperead.. it could happen near multiple roots
            cps = _bs.crossing_points(True)

        ##  merge duplicates (if any)
        cps = _merge_(cps, max(abs(xmin), abs(xmax)))

    ## if no convergency....
    ## if not cps or 1 == len(cps) or split <= 0 : return cps
    if not cps or split <= 0: return cps

    ## come  back to the original spline
    _bs = bs - C

    ## add the current/best estimates of roots
    for x in cps:
        _bs.insert(x)

    ## get internal roots only (no edges)
    _cps = cps
    _bsn = _bs.norm()
    left_root = False
    right_root = False
    if isequal(_bs[0] + _bsn, _bsn):
        left_root = True
        _cps = _cps[1:]
    if isequal(_bs[-1] + _bsn, _bsn):
        right_root = True
        _cps = _cps[:-1]

    cpmin = _cps[0]
    cpmax = _cps[-1]

    dc = cpmax - cpmin

    xmin = _bs.xmin()
    xmax = _bs.xmax()
    dx = xmax - xmin

    ##
    if 1 == len(cps):

        x1 = 0.05 * xmin + 0.95 * cpmin
        x2 = 0.05 * xmax + 0.95 * cpmax

        b1 = _scale_(Ostap.Math.BSpline(_bs, xmin, x1))
        b2 = _scale_(Ostap.Math.BSpline(_bs, x1, x2))
        b3 = _scale_(Ostap.Math.BSpline(_bs, x2, xmax))

        split -= 1
        return _merge_(
            solve(b1, C=0, split=split) + solve(b2, C=0, split=split) +
            solve(b3, C=0, split=split), max(abs(xmin), abs(xmax)))

    dl = 0.05 * min(cpmin - xmin, dc)
    dr = 0.05 * min(xmax - cpmax, dc)

    x_left = cpmin - dl
    x_right = cpmax + dr
    x_mid = 0.5 * (cpmin + cpmax)

    import random
    ntry = 50

    for i in range(ntry):
        if not isequal(_bs(x_left) + _bsn, _bsn): break
        alpha = random.uniform(0.05, 1)
        x_left = max(xmin, cpmin - alpha * dl)

    for i in range(ntry):
        if not isequal(_bs(x_mid) + _bsn, _bsn): break
        alpha = random.uniform(-1, 1)
        x_mid = 0.5 * (cpmin + cpmax) + alpha * dc / 20

    for i in range(ntry):
        if not isequal(_bs(x_right) + _bsn, _bsn): break
        alpha = random.uniform(0.05, 1)
        x_right = min(xmax, cpmax + alpha * dr)

    ## split!
    split -= 1

    if dc > 0.1 * dx:  ##  split

        bs1 = _scale_(Ostap.Math.BSpline(_bs, x_left, x_mid))
        bs2 = _scale_(Ostap.Math.BSpline(_bs, x_mid, x_right))
        roots = _merge_(
            solve(bs1, C=0, split=split) + solve(bs2, C=0, split=split),
            max(abs(xmin), abs(xmax)))

    else:  ##  trim

        bst = _scale_(Ostap.Math.BSpline(_bs, x_left, x_right))
        roots = _merge_(solve(bst, C=0, split=split),
                        max(abs(xmin), abs(xmax)))

    if left_root: roots = (xmin, ) + roots
    if right_root: roots = roots + (xmax, )

    return roots
Example #28
0
def makeWeights(
        dataset,
        plots=[],
        database="weights.db",
        compare=None,  ## comparison function 
        delta=0.01,  ## delta for ``mean''  weight variation
        minmax=0.03,  ## delta for ``minmax'' weight variation
        power=None,  ## auto-determination
        debug=True,  ## save intermediate information in DB
        make_plots=False,  ## make plots 
        tag="Reweighting"):
    """The main  function: perform one re-weighting iteration 
    and reweight ``MC''-data set to looks as ``data''(reference) dataset
    >>> results = makeWeights (
    ... dataset           , ## data source to be  reweighted (DataSet, TTree, abstract source)
    ... plots             , ## reweighting plots
    ... database          , ## datadabse to store/update reweigting results
    ... delta             , ## stopping criteria for `mean`    weight variation
    ... minmax            , ## stopping criteria for `min/max` weight variation
    ... power             , ## effective power to apply to the weigths
    ... debug      = True , ## store debuig information in database
    ... make_plots = True , ## produce useful comparison plots
    ... tag        = 'RW' ) ## tag for better printout
    
    If `make_plots = False`,  it returns the tuple of active reweitings:
    >>> active        = makeWeights ( ... , make_plots = False , ... )
    
    Otherwise it also returns list of comparison plots 
    >>> active, cmp_plots = makeWeights ( ... , make_plots = True  , ... )
    >>> for item in  cmp_plots :
    ...    what    = item.what
    ...    hdata   = item.data
    ...    hmc     = item.mc
    ...    hweight = item.weight
    
    If no more rewighting iteratios required, <code>active</code> is an empty tuple 
    """

    assert 0 < delta, "makeWeights(%s): Invalid value for ``delta''  %s" % (
        tag, delta)
    assert 0 < minmax, "makeWeights(%s): Invalid value for ``minmax'' %s" % (
        tag, minmax)

    from ostap.logger.colorized import allright, attention, infostr
    from ostap.utils.basic import isatty

    nplots = len(plots)
    ## if 1 < nplots :
    ##     import  math
    ##     fudge_factor = math.sqrt ( 1.0 / max ( 2.0 , nplots -  1.0 ) )
    ##     delta   = delta  * fudge_factor
    ##     minmax  = minmax * fudge_factor

    ## list of plots to compare
    cmp_plots = []
    ## reweighting summary table
    header = ('Reweighting', 'wmin/wmax', 'OK?', 'wrms[%]', 'OK?', 'chi2/ndf',
              'ww', 'exp')

    rows = {}
    save_to_db = []
    ## number of active plots for reweighting
    for wplot in plots:

        what = wplot.what  ## variable/function to plot/compare
        how = wplot.how  ## weight and/or additional cuts
        address = wplot.address  ## address in database
        hdata0 = wplot.data  ## original "DATA" object
        hmc0 = wplot.mc_histo  ## original "MC"   histogram
        ww = wplot.w  ## relative weight
        projector = wplot.projector  ## projector for MC data
        ignore = wplot.ignore  ## ignore for weigtht building?
        #
        # normalize the data
        #
        hdata = hdata0
        if isinstance(hdata, ROOT.TH1): hdata = hdata.density()

        # =====================================================================
        ## make a plot on (MC) data with the weight
        # =====================================================================
        hmc0 = projector(dataset, hmc0, what, how)

        st = hmc0.stat()
        mnmx = st.minmax()
        if iszero(mnmx[0]):
            logger.warning("%s: statistic goes to zero %s/``%s''" %
                           (tag, st, address))
        elif mnmx[0] <= 0:
            logger.warning("%s: statistic is negative  %s/``%s''" %
                           (tag, st, address))

        # =====================================================================
        ## normalize MC
        # =====================================================================
        hmc = hmc0.density()

        # =====================================================================
        ## calculate  the reweighting factor : a bit conservative (?)
        #  this is the only important line
        # =====================================================================

        #  try to exploit finer binning if/when possible
        hboth = isinstance(hmc, ROOT.TH1) and isinstance(hdata, ROOT.TH1)

        if   hboth and 1 == hmc.dim () and 1 == hdata.dim () and \
               len ( hmc ) >= len( hdata ) :
            w = (1.0 / hmc) * hdata  ## NB!
        elif hboth and 2 == hmc.dim () and 2 == hdata.dim () and \
                 ( hmc.binsx() >= hdata.binsx() ) and \
                 ( hmc.binsy() >= hdata.binsy() ) :
            w = (1.0 / hmc) * hdata  ## NB!
        elif hboth and 3 == hmc.dim () and 3 == hdata.dim () and \
                 ( hmc.binsx() >= hdata.binsx() ) and \
                 ( hmc.binsy() >= hdata.binsy() ) and \
                 ( hmc.binsz() >= hdata.binsz() ) :
            w = (1.0 / hmc) * hdata  ## NB!
        else:
            w = hdata / hmc  ## NB!

        # =====================================================================
        ## scale & get the statistics of weights
        w /= w.stat().mean().value()
        cnt = w.stat()
        #
        mnw, mxw = cnt.minmax()
        wvar = cnt.rms() / cnt.mean()
        good1 = wvar.value() <= delta
        good2 = abs(mxw - mnw) <= minmax
        good = good1 and good2  ## small variance?
        #

        c2ndf = 0
        for i in w:
            c2ndf += w[i].chi2(1.0)
        c2ndf /= (len(w) - 1)

        ## build  the row in the summary table
        row = address  ,  \
              '%-5.3f/%5.3f' % ( cnt.minmax()[0]    , cnt.minmax()[1] ) , \
              allright ( '+' ) if good2 else attention ( '-' ) , \
              (wvar * 100).toString('%6.2f+-%-6.2f') , \
              allright ( '+' ) if good1 else attention ( '-' ) , '%6.2f' % c2ndf

        ## make plots at the start of  each iteration?
        if make_plots:
            item = ComparisonPlot(what, hdata, hmc, w)
            cmp_plots.append(item)

        row = tuple(list(row) + ['%4.3f' % ww if 1 != ww else ''])

        rows[address] = row

        #
        ## make decision based on the variance of weights
        #
        mnw, mxw = cnt.minmax()
        if (not good) and (not ignore):  ## small variance?
            save_to_db.append((address, ww, hdata0, hmc0, hdata, hmc, w))

        # =====================================================================
        ## make a comparison (if needed)
        # =====================================================================
        if compare: compare(hdata0, hmc0, address)

    active = tuple([p[0] for p in save_to_db])
    nactive = len(active)

    if power and callable(power):
        eff_exp = power(nactive)
    elif isinstance(power, num_types) and 0 < power <= 1.5:
        eff_exp = 1.0 * power
    elif 1 == nactive and 1 < len(plots):
        eff_exp = 0.95
    elif 1 == nactive:
        eff_exp = 1.00
    else:
        eff_exp = 1.10 / max(nactive, 1)

    while database and save_to_db:

        entry = save_to_db.pop()

        address, ww, hd0, hm0, hd, hm, weight = entry

        cnt = weight.stat()
        mnw, mxw = cnt.minmax()

        ## avoid too large or too small  weights
        for i in weight:
            w = weight[i]
            if w.value() < 0.5:
                weight[i] = VE(0.5, w.cov2())
            elif w.value() > 2.0:
                weight[i] = VE(2.0, w.cov2())

        if 1 < nactive and 1 != ww:
            eff_exp *= ww
            logger.info("%s: apply ``effective exponent'' of %.3f for ``%s''" %
                        (tag, eff_exp, address))

        if 1 != eff_exp and 0 < eff_exp:
            weight = weight**eff_exp
            row = list(rows[address])
            row.append('%4.3f' % eff_exp)
            rows[address] = tuple(row)

        with DBASE.open(database) as db:

            db[address] = db.get(address, []) + [weight]

            if debug:
                addr = address + ':REWEIGHTING'
                db[addr] = db.get(addr, []) + list(entry[2:])

        del hd0, hm0, hd, hm, weight, entry

    table = [header]
    for row in rows:
        table.append(rows[row])

    import ostap.logger.table as Table
    logger.info(
        '%s, active:#%d \n%s ' %
        (tag, nactive,
         Table.table(table, title=tag, prefix='# ', alignment='lccccccc')))

    cmp_plots = tuple(cmp_plots)
    return (active, cmp_plots) if make_plots else active
Example #29
0
    ]

    for o in functions:

        fun = o[0]  ## function
        der = o[1]  ## derivative
        x = o[2]  ## argument

        logger.info(80 * '*')

        for i in range(1, 6):

            res = derivative(fun, x, 1.e-20, i, err=True)
            f1 = res
            d = der(x)  ## the exact value for derivative
            if iszero(d):
                logger.info('Rule=%2d %s %s %s' % (2 * i + 1, f1, d,
                                                   (f1.value() - d)))
            else:
                logger.info('Rule=%2d %s %s %s' % (2 * i + 1, f1, d,
                                                   (f1.value() - d) / d))

    logger.info(80 * '*')

    ## the function
    func = math.sin
    ## analysitical derivative
    deriv_a = math.cos
    ## numerical first derivative
    deriv_1 = Derivative(func, order=5)
    ## numerical second derivative
Example #30
0
def makeWeights  ( dataset                 ,
                   plots    = []           ,
                   database = "weights.db" ,
                   compare  = None         ,   ## comparison function 
                   delta    = 0.001        ,   ## delta for ``mean''  weigth variation
                   minmax   = 0.05         ,   ## delta for ``minmax'' weigth variation
                   power    = 0            ,   ## auto-determination
                   debug    = True         ) : ## save intermediate information in DB 

    assert 0 < delta  , "Reweighting: Invalid value for ``delta''  %s" % delta 
    assert 0 < minmax , "Reweighting: Invalid value for ``minmax'' %s" % minmax 

    power   = power if power >= 1 else len ( plots ) 

    nplots  = len ( plots )
    if 1 < nplots :
        import  math
        fudge_factor = math.sqrt ( 1.0 / max ( 2.0 , nplots -  1.0 ) )
        delta   = delta  * fudge_factor
        minmax  = minmax * fudge_factor
        

    save_to_db = [] 
    ## number of active plots for reweighting
    active = 0
    ## loop over plots 
    for wplot in plots  :
        
        what    = wplot.what       ## variable/function to plot/compare 
        how     = wplot.how        ## weight and/or additional cuts 
        address = wplot.address    ## address in database 
        hdata0  = wplot.data       ## original "DATA" object 
        hmc0    = wplot.mc_histo   ## original "MC"   histogram 
        ww      = wplot.w          ## relative weight 
        #
        # normailze the data
        #
        hdata = hdata0
        if isinstance ( hdata , ROOT.TH1 ) :  hdata = hdata.density ()
        
        #
        ## make a plot on (MC) data with the weight
        # 
        dataset.project ( hmc0 , what , how )
        
        st   = hmc0.stat()
        mnmx = st.minmax()
        if iszero ( mnmx[0] ) :
            logger.warning ( "Reweighting: statistic goes to zero %s/``%s''" % ( st , address ) ) 
            
        #
        ## normalize MC
        #
        hmc = hmc0.density() 
        
        #
        ## calculate  the reweighting factor : a bit conservative (?)
        # 
        #  this is the only important line
        #
        #  try to exploit finer binning if possible

        if len ( hmc ) >= len( hdata )  : w =  ( 1.0 / hmc ) * hdata ## NB!      
        else                            : w =  hdata / hmc           ## NB!
        
        ## scale & get the statistics of weights 
        w   /= w.stat().mean().value()
        cnt  = w.stat()
        #
        wvar = cnt.rms()/cnt.mean()
        logger.info ( 'Reweighting: %24s: mean/(min,max):%20s/(%.3f,%.3f) RMS:%s[%%]' %
                      ( "``" + address + "''"  ,
                        cnt.mean().toString('(%.2f+-%.2f)') ,
                        cnt.minmax()[0] ,
                        cnt.minmax()[1] , (wvar * 100).toString('(%.2f+-%.2f)') ) ) 
        #
        ## make decision based on the variance of weights 
        #
        mnw , mxw = cnt.minmax()
        if wvar.value() <= delta and abs ( mxw - mnw ) <= minmax : ## small variance? 
            logger.info("Reweighting: No more reweights for ``%s'' [%.2f%%]/[(%+.1f,%+.1f)%%]" % \
                        ( address , wvar * 100 , ( mnw - 1 ) * 100 ,  ( mxw - 1 ) * 100 ) )
            del w , hdata , hmc 
        else :
            save_to_db.append ( ( address , ww , hdata0 , hmc0 , hdata , hmc , w ) ) 
        #
        ## make a comparison (if needed)
        # 
        if compare : compare ( hdata0 , hmc0 , address )

    
    ## for single reweighting 
    if 1 == nplots : power = 1
    
    if power != nplots :
        logger.info ( "Reweighting: ``power'' is %g/#%d"  % ( power , nplots  ) )

    active = len ( save_to_db )
    if active !=  nplots :
        logger.info ( "Reweighting: number of ``active'' reweights %s/#%d"  % ( active , nplots ) )
        if database and save_to_db : 
            power += ( nplots - active )
            logger.info  ("Reweighting: ``power'' is changed to %g" %  power ) 
    
    while database and save_to_db :

        entry = save_to_db.pop() 
        
        address, ww , hd0, hm0, hd , hm , weight = entry  

        eff_exp = 1.0 / power
        if 1 != nplots and 1 != ww :
            eff_exp *= ww
            logger.info  ("Reweighting: apply ``effective exponent'' of %.3f for ``%s''" % ( eff_exp  , address ) )
            
        if 1 != eff_exp and 0 < eff_exp : 
            weight = weight ** eff_exp

        ## print 'WEIGHT stat', eff_exp, weight.stat()
        
        ## hmmmm... needed ? yes! 
        #if 1 < power : weight = weight ** ( 1.0 / power )
        
        ## relative importance
        #if 1 != ww :
        #    logger.info  ("Reweighting: apply ``relative importance factor'' of %.3g for ``'%s'" % ( ww , address ) )
        #    weight = weight ** ww 

        with DBASE.open ( database ) as db :
            
            db[address] = db.get( address , [] ) + [ weight ]
            
            if debug :
                addr        = address + ':REWEIGHTING'
                db [ addr ] = db.get ( addr , [] ) + list ( entry[2:] )
                
        del hd0, hm0 , hd , hm , weight , entry 
        
    return active