I have 2 functions that read a csv file and count the following as checks:

1. number of rows in that csv
2. number of rows that have a null value in the 'ID' column

I am trying to create a dataframe that looks like this

Checks	Summary	Findings
Check #1	Number of records on file	function #1 results (Number of records on file: 10)
Check #2	Number of records missing an ID	function #2 results (Number of records missing an ID: 2)

function 1 looks like this:

def function1():
    with open('data.csv') as file:
        record_number = len(list(file))
        print("Number of records on file:",record_number)
function1()

and outputs "Number of records on file: 10"

function 2 looks like this:

def function2():
    df = pd.read_csv('data.csv', low_memory=False)
    missing_id = df["IDs"].isna().sum()
    print("Number of records missing an ID:", missing_id)
function2()

and outputs "Number of records missing an ID: 2"

I attempt to create a dictionary first and create my dictionary

table = {
   'Checks' : ['Check #1', 'Check #2'],
    'Summary' : ['Number of records on file', 'Number of records missing an ID'],
    'Findings' : [function1, function2]
}
df = pd.DataFrame(table)
df

However, this is what the dataframe looks like:

Checks	Summary	Findings
Check #1	Number of records on file	<function function1 at 0x7efd2d76a730>
Check #2	Number of records missing an ID	<function2 at 0x7efd25cd0b70>

Is there any way to make it so that my Findings column outputs the actual results as seen above?

CodePudding user response：

The reason is that you're printing the function objects, and not their results:

function1 != function1()

So for your case you need:

table = {
   'Checks' : ['Check #1', 'Check #2'],
    'Summary' : ['Number of records on file', 'Number of records missing an ID'],
    'Findings' : [function1(), function2()]
}
df = pd.DataFrame(table)
df

Edit: Oh damn and I also missed what the other user commented. You definitely need to return a value from your functions as well :)

CodePudding user response：

You need to change your functions so they return values, not output them, that is do

def function1():
    with open('data.csv') as file:
        record_number = len(list(file))
        return record_number

and

def function2():
    df = pd.read_csv('data.csv', low_memory=False)
    return df["IDs"].isna().sum()

and call these functions like so

table = {
   'Checks' : ['Check #1', 'Check #2'],
    'Summary' : ['Number of records on file', 'Number of records missing an ID'],
    'Findings' : [function1(), function2()]
}
df = pd.DataFrame(table)
df

CodePudding user response：

For expected ouput add return with f-strings to both functions, in DataFrame call functions with parentheses:

def function1():
    with open('data.csv') as file:
        record_number = len(list(file))
        return f"function #1 results (Number of records on file: {record_number})")


def function2():
    df = pd.read_csv('data.csv', low_memory=False)
    missing_id = df["IDs"].isna().sum()
    return f"function #2 results (Number of records missing an ID: {missing_id})")


table = {
   'Checks' : ['Check #1', 'Check #2'],
    'Summary' : ['Number of records on file', 'Number of records missing an ID'],
    'Findings' : [function1(), function2()]
}
df = pd.DataFrame(table)

Solution with one function:

def function():
    with open('data.csv') as file:
        record_number = len(list(file))
        missing_id = df["IDs"].isna().sum()
        
        return [f"function #1 results (Number of records on file: {record_number})"),
                f"function #2 results (Number of records missing an ID: {missing_id})")]


table = {
   'Checks' : ['Check #1', 'Check #2'],
    'Summary' : ['Number of records on file', 'Number of records missing an ID'],
    'Findings' : function()
}
df = pd.DataFrame(table)