我试图在两列中的任意一列中搜索特定值，当找到目标值时，将第三列中的数字从正数更改为负数或从负数更改为正数。
te1 = df.loc[df['Transaction Event'] == 'Exercise']
te2 = df.loc[df['Transaction Event'] == 'Assignment']
te3 = df.loc[df['Transaction Event'] == 'Expiration']
an1 = df.loc[df['Action'] == 'Delete']
nq = df['Net Quantity']
var1 = df[(df['Transaction Event'] == 'Exercise') | (df['Transaction Event'] == 'Assignment') | (df['Transaction Event'] == 'Expiration') | (df['Action'] == 'Delete')]
df.loc[df[var1], nq] = df.loc[df[var1], nq] * -1
运行此代码会返回以下错误：
---------------------------------------------------------------------------
ValueError Traceback (most recent call last)
<ipython-input-282-01dbb8066276> in <module>()
6 var1 = df[(df['Transaction Event'] == 'Exercise') | (df['Transaction Event'] == 'Assignment') | (df['Transaction …