如何用Python统计符合特定条件的上升循环峰值数量？

原代码的问题分析 #

1. 分割逻辑错误：使用np.split(cycle, np.where(np.diff(cycle) < 0)[0] + 1)会将每次数值下降的位置都切割数组，得到的子数组大多是循环的片段（比如仅上升阶段、仅下降阶段），并非完整的上升-下降循环。
2. 条件判断完全偏离需求：
   • min(unit) > 0直接排除了所有下限小于5的情况（比如0、3这类符合要求的低点），导致目标循环被过滤。
   • max(unit) < 25会包含大量峰值超过22的循环，错误统计了不符合要求的片段。
3. 未定义完整循环：没有以“低点→峰值→低点”的完整周期作为判断单位，而是误将片段当成循环。

修正后的代码实现 #

以下代码基于“完整上升循环=从低点（<5）开始→上升到峰值→下降回到低点（<5）”的逻辑，严格匹配你的统计条件：

cycle = [0, 14,  9,  0,  0,  7,  0,  0, 12, 16, 15, 11,  7, 20, 24, 13, 13,
       14, 19, 13, 12, 10,  7,  3,  3,  3, 25, 14, 14, 14,  7, 24, 20, 20,
       21, 20, 20, 20, 20, 20, 21, 16, 11, 11, 18, 22, 22, 20, 19, 19, 18,
       15, 20, 23, 21, 23, 24, 15, 16, 19, 25, 24,  0, 20, 23, 24, 23, 22,
       21, 23, 25, 28, 24, 23, 23, 17,  7, 11, 21, 25, 25, 25, 25, 25, 25,
       15, 13,  9,  0, 21, 10, 18, 25, 25, 26, 23, 25, 23, 25, 27, 25, 12,
        0,  0,  0, 19, 22, 24, 25, 25, 24, 24, 23, 23, 16, 19, 23, 24, 24,
       17,  8,  0,  9,  7, 11, 18, 20, 23, 23, 24, 25, 25, 25, 17, 24, 24,
       25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 16,  0,  7, 14, 21, 26, 26,
       27, 28, 27, 15, 25, 26, 25, 25, 25, 24, 25, 25, 24, 26, 26, 26, 23]

valid_cycles = []
start_idx = 0
n = len(cycle)

# 遍历数组，以<5的低点作为循环的起止标志
for i in range(1, n):
    # 当从非低点进入低点时，视为一个循环结束
    if cycle[i] < 5 and cycle[i-1] >= 5:
        current_cycle = cycle[start_idx:i+1]
        cycle_min = min(current_cycle)
        cycle_max = max(current_cycle)
        # 匹配需求条件：下限<5，上限在21-22之间
        if cycle_min < 5 and 21 <= cycle_max <= 22:
            valid_cycles.append(current_cycle)
        start_idx = i + 1

# 处理数组末尾的剩余片段
if start_idx < n:
    current_cycle = cycle[start_idx:]
    cycle_min = min(current_cycle)
    cycle_max = max(current_cycle)
    if cycle_min < 5 and 21 <= cycle_max <= 22:
        valid_cycles.append(current_cycle)

# 输出结果
print(f"符合条件的循环数量：{len(valid_cycles)}")
for idx, cyc in enumerate(valid_cycles):
    print(f"循环{idx+1}：{cyc}")
    print(f"  下限（最小值）：{min(cyc)}，上限（最大值）：{max(cyc)}\n")

代码说明 #

1. 循环识别逻辑：以数值从≥5降到<5的节点作为循环结束标志，确保每个子数组是完整的“低点→峰值→低点”循环。
2. 条件匹配：严格检查两个核心条件：
   • 循环的最小值（下限）小于5
   • 循环的最大值（上限）处于21到22之间（包含21和22）
3. 新手友好：纯Python实现，无需复杂的numpy分割逻辑，逻辑清晰易懂。

内容的提问来源于stack exchange，提问作者user20759431