[FIXED] if row is missing, data == 0. if not missing use default value

Issue

def compute(tick):
    df = pd.read_csv(f'{tick}.csv')
    a = df.loc['a'].sum()
    b = df.loc['b'].sum()
    c = df.loc['c'].sum()
    d = (a + b) / c
    return d

in some dataframes there is no row 'b', so it returns KeyError. Then I tried following code, but it doesnt work, anyone can help me provide a solution to this problem?

def compute(tick):
    df = pd.read_csv(f'{tick}.csv')
    a = df.loc['a'].sum()
    if df.loc['b'].isnull():
        b == 0
    else:
        b = df.loc['b'].sum()
    c = df.loc['c'].sum()
    d = (a + b) / c
    return d

Solution

Try using this

def compute(tick):
    df = pd.read_csv(f'{tick}.csv')
    
    if b in df.columns: #Check if column b exists.
        b = df.loc['b'].sum()
    else:
        b = 0

    a = df.loc['a'].sum()
    c = df.loc['c'].sum()
    d = (a + b) / c
    return d

Answered By - Raymond Toh