python - 为什么每次我尝试运行 Python 程序时 Eclipse 都会要求我输入 'ant build'？

Question

我不熟悉编程和使用 pydev 在 eclipse 中运行我的 python。我正在使用 Eclipse EE 和 Python 2.7.3 我尝试运行的代码在这里:

def evaluate_poly(poly, x):

        sumPoly = 0

        for i in range(0,len(poly)):
            #calculate each term and add to sum.
            sumPoly = sumPoly+(poly[i]*x**i)
        return sumPoly




def compute_deriv(poly):

    derivTerm = ()

    #create a new tuple by adding a new term each iteration, assign to derivTerm each time.
    for i in range(0,len(poly)):
    #i is the exponent, poly[i] is the coefficient,
    #coefficient of the derivative is the product of the two.
        derivTerm = derivTerm + (poly[i]*i,)
    return derivTerm



def compute_root(poly, x_0, epsilon):

    #define root to make code simpler.
    root = evaluate_poly(poly,x_0)
    iterations = 0

    #until root (evaluate_poly) is within our error range of 0...
    while (root > epsilon) or (root < -epsilon):
    #...apply newton's method, calculate new root, and count iterations.
        x_0 = (x_0 - ((root)/(evaluate_poly(compute_deriv(poly),x_0))))
        root = evaluate_poly(poly,x_0)
        iterations = iterations + 1
    return (x_0,iterations)

print compute_root((4.0,3.0,2.0),0.1,0.0001)

每次我尝试运行此 eclipse 时都会要求我进行 ant 构建。当我单击确定时，没有任何反应。只有当我在函数内部运行函数时才会发生这种情况，看起来非常基本的代码不是问题。出了什么问题，我该如何解决？

Answer 1

如果你只有函数，python 不会做任何事情。它不会无缘无故地运行任意函数。如果你想打印一些东西，你需要调用你的函数之一。最好的方法是将其添加到代码的底部:

if __name__ == '__main__':
    evaluate_poly([1, 2, 3], 4)