Skip to main content

Conditionally update values in a pandas dataframe while moving across successive columns

I have a pandas DataFrame of membership records that contains some entry errors (see table below for a few examples). Some members were incorrectly identified as "Joined" when they were in fact "Renewal" and/or listed as "Joined" multiple times. I want to correct these errors by turning "Joined" into "Renewal" and vice-verse as appropirate based on the column year.

MemTransType2009 MemTransType2010 MemTransType2011 MemTransType2012 MemTransType2013 MemTransType2014 MemTransType2015
NaN NaN Joined Renewal Renewal Joined Renewal
NaN Joined Renewal NaN Joined Renewal Renewal
Joined Renewal Renewal Renewal Renewal Renewal Renewal
NaN NaN Renewal Joined Renewal Renewal NaN

Using np.where and a loop that updates the row I can make corrections column by column. For example:

Years = ['MemTransType2009', 'MemTransType2010', 'MemTransType2011', 'MemTransType2012', 'MemTransType2013', 'MemTransType2014', 'MemTransType2015']

for col in df[Years[1:]]:
    df[col] = np.where(((df[Years[0]] == 'Joined') & (df[col] == 'Joined')), 'Renewal', df[col])

for col in TEST[Years[2:]]:
    df[col] = np.where(((df[Years[1]] == 'Joined') & (df[col] == 'Joined')), 'Renewal', df[col])

etc...

will get rid of any duplicating "Joined", but I'm not skilled enough to do it for all columns at once. Right now I'm manually updating for each successive column.

I've tried several variations of a more complex loop but I get no response, an error, or accidently overwrite all the data.

For example,

Years = ['MemTransType2009', 'MemTransType2010', 'MemTransType2011', 'MemTransType2012', 'MemTransType2013', 'MemTransType2014', 'MemTransType2015']

for x in range(len(Years)):
    for col in df[Years[x+1]]:
        df[col] = np.where(((df[Years[x]] == 'Joined') & (df[col] == 'Joined')), 'Renewal', df[col])

Because I have to move forward in time, I believe I need to take the columns sequentially. Is there a way to update the records en masse where values associated with the first column are checked initially and then move on to the next column? Or is there alternative approach?

Thank you for any suggestions / examples.



source https://stackoverflow.com/questions/72764336/conditionally-update-values-in-a-pandas-dataframe-while-moving-across-successive

Comments

Popular posts from this blog

Where and how is this Laravel kernel constructor called? [closed]

Where and how is this Laravel kernel constructor called? public fucntion __construct(Application $app, $Router $roouter) { } I have read the documentation and some online tutorial but I can find any clear explanation. I am learning Laravel and I am wondering where does this kernel constructor receives its arguments from. "POSTMOTERM" CLARIFICATION: Here is more clarity.I have checked the boostrap/app.php and it is only used for boostrapping the interfaces into the container class. What is not clear to me is where and how the Kernel class is instatiated and the arguments passed to the object calling the constructor.Something similar to; obj = new kernel(arg1,arg2) or, is the framework using some magic functions somewhere? Special gratitude to those who burn their eyeballs and brain cells on this trivia before it goes into a full blown menopause alias "MARKED AS DUPLICATE". To some of the itchy-finger keyboard warriors, a.k.a The mods,because I believe in th...

Why is my reports service not connecting?

I am trying to pull some data from a Postgres database using Node.js and node-postures but I can't figure out why my service isn't connecting. my routes/index.js file: const express = require('express'); const router = express.Router(); const ordersCountController = require('../controllers/ordersCountController'); const ordersController = require('../controllers/ordersController'); const weeklyReportsController = require('../controllers/weeklyReportsController'); router.get('/orders_count', ordersCountController); router.get('/orders', ordersController); router.get('/weekly_reports', weeklyReportsController); module.exports = router; My controllers/weeklyReportsController.js file: const weeklyReportsService = require('../services/weeklyReportsService'); const weeklyReportsController = async (req, res) => { try { const data = await weeklyReportsService; res.json({data}) console...

How to show number of registered users in Laravel based on usertype?

i'm trying to display data from the database in the admin dashboard i used this: <?php use Illuminate\Support\Facades\DB; $users = DB::table('users')->count(); echo $users; ?> and i have successfully get the correct data from the database but what if i want to display a specific data for example in this user table there is "usertype" that specify if the user is normal user or admin i want to user the same code above but to display a specific usertype i tried this: <?php use Illuminate\Support\Facades\DB; $users = DB::table('users')->count()->WHERE usertype =admin; echo $users; ?> but it didn't work, what am i doing wrong? source https://stackoverflow.com/questions/68199726/how-to-show-number-of-registered-users-in-laravel-based-on-usertype