有关float类型表示范围的探究

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# -*- encoding: utf-8 -*-

import random
from matplotlib import pyplot as plt


def main():
    # 从000000开始到 00001101010....，二进制递增顺序查看对应的float表示范围
    # for i in range(1000000):
    #     binStr = str(bin(i))[2:]
    #     binStr = "0" * (32 - len(binStr)) + binStr
    #     print(binStr)
    #     print(strToFloat32(binStr))

    # print(strToFloat32("11111111111111111111111111111111"))
    # print(strToFloat32("11111111111111111111111111111110"))
    # print(strToFloat32("11111111111111111111111111111101"))
    # print(strToFloat32("11111111111111111111111111111100"))
    # print(strToFloat32("11111111111111111111111111111001"))

    arr = []
    for i in range(10000):
        arr.append(randFloat32())
    minNum = min(arr)
    maxNum = max(arr)
    print(minNum, maxNum)
    div = 50  # 把这一整段区间分成很多段，分别看每一段包含的数量
    partLen = (maxNum - minNum) / div
    y = []
    x = []
    for i in range(div):
        left = minNum + partLen * i
        count = 0
        for n in arr:
            if left <= n < left + partLen:
                count += 1
        y.append(count)
        x.append(f"{int(left)}")
        print(f"{count} /t/t{int(left)}~{int(left + partLen)}", )

    plt.plot(x, y)
    plt.xticks(x, rotation=45)
    plt.show()
    ...


def strBinToInt(string):
    return eval(f"0b{string}")


def strToFloat32(string):
    """把一个32位二进制字符流解析成float类型"""
    # 解析二进制字符流
    flag = string[0]
    head = string[1:9]
    tile = string[9:]
    headNumber = strBinToInt(head)
    tile = "1" + tile
    left = strBinToInt(tile[:headNumber + 1])
    right = 0.0
    rightStr = tile[headNumber + 1:]
    for i, char in enumerate(rightStr):
        if char == "1":
            right += 0.5 ** i
            ...
    if flag == "0":
        return left + right
    else:
        return -(left + right)


def randFloat32():
    """随机生成一个float32的浮点数"""
    randStr = ""
    for i in range(32):
        if random.random() < 0.5:
            randStr += "0"
        else:
            randStr += "1"
    return strToFloat32(randStr)


if __name__ == '__main__':
    main()