我如何在0和1之间迭代0.1步?

这表示step参数不能为零:

for i in range(0, 1, 0.1):
    print(i)

当前回答

下面是我的解决方案,它可以很好地使用float_range(- 1,0,0.01),并且没有浮点表示错误。它不是很快,但工作得很好:

from decimal import Decimal

def get_multiplier(_from, _to, step):
    digits = []
    for number in [_from, _to, step]:
        pre = Decimal(str(number)) % 1
        digit = len(str(pre)) - 2
        digits.append(digit)
    max_digits = max(digits)
    return float(10 ** (max_digits))


def float_range(_from, _to, step, include=False):
    """Generates a range list of floating point values over the Range [start, stop]
       with step size step
       include=True - allows to include right value to if possible
       !! Works fine with floating point representation !!
    """
    mult = get_multiplier(_from, _to, step)
    # print mult
    int_from = int(round(_from * mult))
    int_to = int(round(_to * mult))
    int_step = int(round(step * mult))
    # print int_from,int_to,int_step
    if include:
        result = range(int_from, int_to + int_step, int_step)
        result = [r for r in result if r <= int_to]
    else:
        result = range(int_from, int_to, int_step)
    # print result
    float_result = [r / mult for r in result]
    return float_result


print float_range(-1, 0, 0.01,include=False)

assert float_range(1.01, 2.06, 5.05 % 1, True) ==\
[1.01, 1.06, 1.11, 1.16, 1.21, 1.26, 1.31, 1.36, 1.41, 1.46, 1.51, 1.56, 1.61, 1.66, 1.71, 1.76, 1.81, 1.86, 1.91, 1.96, 2.01, 2.06]

assert float_range(1.01, 2.06, 5.05 % 1, False)==\
[1.01, 1.06, 1.11, 1.16, 1.21, 1.26, 1.31, 1.36, 1.41, 1.46, 1.51, 1.56, 1.61, 1.66, 1.71, 1.76, 1.81, 1.86, 1.91, 1.96, 2.01]

其他回答

[x * 0.1 for x in range(0, 10)] 

在Python 2.7x中给出的结果为:

[0.0, 0.1, 0.2, 0.30000000000000004, 0.4, 0.5, 0.6000000000000001, 0.7000000000000001, 0.8, 0.9]

但如果你用:

[ round(x * 0.1, 1) for x in range(0, 10)]

给你想要的:

[0.0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9]

下面是一个使用itertools的解决方案:

import itertools

def seq(start, end, step):
    if step == 0:
        raise ValueError("step must not be 0")
    sample_count = int(abs(end - start) / step)
    return itertools.islice(itertools.count(start, step), sample_count)

使用的例子:

for i in seq(0, 1, 0.1):
    print(i)

如果你经常这样做,你可能想保存生成的列表r

r=map(lambda x: x/10.0,range(0,10))
for i in r:
    print i

Range()只能处理整数,不能处理浮点数。

使用一个列表推导式来获得一个步骤列表:

[x * 0.1 for x in range(0, 10)]

更一般地说,生成器理解最小化内存分配:

xs = (x * 0.1 for x in range(0, 10))
for x in xs:
    print(x)

在'xrange([start], stop[, step])'基础上,你可以定义一个生成器,它接受并生成你选择的任何类型(坚持支持+和<的类型):

>>> def drange(start, stop, step):
...     r = start
...     while r < stop:
...         yield r
...         r += step
...         
>>> i0=drange(0.0, 1.0, 0.1)
>>> ["%g" % x for x in i0]
['0', '0.1', '0.2', '0.3', '0.4', '0.5', '0.6', '0.7', '0.8', '0.9', '1']
>>>