Dropping rows at specific minutes-CodePudding

I am trying to drop rows at specific minutes ( 05,10, 20 ) I have datetime as an index

df5['Year'] = df5.index.year
df5['Month'] = df5.index.month
df5['Day']= df5.index.day
df5['Day_of_Week']= df5.index.day_name()
df5['hour']= df5.index.strftime('%H')
df5['Min']= df5.index.strftime('%M')
df5

Then I run below

def clean(df5):
for i in range(len(df5)):
    hour = pd.Timestamp(df5.index[i]).hour
    minute = pd.Timestamp(df5.index[i]).minute
    if df5 = df5[(df5.index.minute ==5) | (df5.index.minute == 10)| (df5.index.minute == 20)]
        df.drop(axis=1, index=i, inplace=True)

it returnes invalid syntax error.

CodePudding user response：

Here looping is not necessary, also not recommended.

Use DatetimeIndex.minute with Index.isin and inverted mask by ~ filtering in boolean indexing:

df5 = df5[~df5.index.minute.isin([5, 10, 20])]

For reuse column df5['Min'] use strings values:

df5 = df5[~df5['Min'].isin(['05', '10', '20'])]

All together:

def clean(df5):
    return df5[~df5.index.minute.isin([5, 10, 20])]

CodePudding user response：

You can just do it using boolean indexing, assuming that the index is already parsed as datetime.

df5 = df5[~((df5.index.minute == 5) | (df5.index.minute == 10) | (df5.index.minute == 20))]

Or the opposite of the same answer:

df5 = df5[(df5.index.minute != 5) | (df5.index.minute != 10) | (df5.index.minute != 20)]

CodePudding user response：

Generally speaking, the right synthax to combine a logic OR inside an IF statement is the following:

    today = 'Saturday'
    
    if today=='Sunday' OR today=='Saturday':
        print('Today is off. Rest at home')

In your case, you should probably use something like this:

if df5 == df5[(df5.index.minute ==5)] OR df5[(df5.index.minute ==10)]
        ......

FINAL NOTE:

You made some mistakes using == and =

In Python (and many other programming languages), a single equal mark = is used to assign a value to a variable, whereas two consecutive equal marks == is used to check whether 2 expressions give the same value .

= is an assignment operator

== is an equality operator