python计算牛顿迭代多项式，python牛顿多项式,''' p = eval

python计算牛顿迭代多项式，python牛顿多项式,''' p = eval

''' p = evalPoly(a,xData,x).    Evaluates Newton's polynomial p at x. The coefficient    vector 'a' can be computed by the function 'coeffts'.    a = coeffts(xData,yData).    Computes the coefficients of Newton's polynomial.'''    def evalPoly(a,xData,x):    n = len(xData) - 1  # Degree of polynomial    p = a[n]    for k in range(1,n+1):        p = a[n-k] + (x -xData[n-k])*p    return pdef coeffts(xData,yData):    m = len(xData)  # Number of data points    a = yData.copy()    for k in range(1,m):        a[k:m] = (a[k:m] - a[k-1])/(xData[k:m] - xData[k-1])    return a