如何检测pyspark中的单调下降

from pyspark.sql import SparkSession
from pyspark.sql.functions import lag, col
from pyspark.sql.window import Window

spark = SparkSession.builder.appName("Monotonic Decrease Detection").getOrCreate()

data = [(1, 10), (2, 9), (3, 8), (4, 7), (5, 6), (6, 5), (7, 4), (8, 3), (9, 2), (10, 1)]
df = spark.createDataFrame(data, ["id", "value"])

windowSpec = Window.orderBy("id")
df = df.withColumn("diff", col("value") - lag("value").over(windowSpec))

df = df.filter(col("diff") <= 0)

if df.count() > 0:
    print("存在单调下降的情况")
else:
    print("不存在单调下降的情况")