python - Using one DataFrame as index for another DataFrame in pandas -


still trying figure out how perform operations multiple dataframes form pandas, in python.

i have following 3 dataframes (d1, d2, , d3): enter image description here

for every user in user_id, need use values in columns df2 index of 'weeks' in df3, , multiply them respective values in df1.

e.g.: user 163, column measurements has value 0.0 (from df2). look-up in df3 @ week 0.0 2. final value computed user/column 2(from df1) times 2 = 4.

i need estimate users in user_id , columns (activity, nutrition, etc.)

any ideas?

i have been playing .apply find hard structure problem correctly.

the key, think, put data together. can work separately iterating , going , forth, easier , robust use pandas merge functionality, this:

import pandas pd  data1 = {'user_id':[163], 'measurements':[2.0]} data2 = {'user_id':[163], 'measurements':[0.0]} data3 = {'weeks':[0.0], 'measurements':[2.0]}  df1 = pd.dataframe(data1) df2 = pd.dataframe(data2) df3 = pd.dataframe(data3)  df = df1.merge(df2, on='user_id', how='outer', suffixes=['_df1', '_df2']) df = df.merge(df3, left_on='measurements_df2', right_on='weeks',               how='outer', suffixes=['', '_df3']) df['new_val'] = df['measurements_df1'] * df['measurements']  in [13]: df out[13]:    measurements_df1  user_id  measurements_df2  measurements  weeks  new_val 0               2.0      163               0.0           2.0    0.0      4.0

in future it's easier if give reproducible example work with, if can include errors tried, in case know mean being hard figure out how structure question properly. suggest book creator of pandas, wes mckinney.


Comments

Post a Comment

Popular posts from this blog

asynchronous - C# WinSCP .NET assembly: How to upload multiple files asynchronously -

i using winscp .net assembly uploading files. want upload multiple files asynchronous way. have created method works single upload. public class uploadingdata { private sessionoptions _sessionoptions; private session _session; //connection etc private void onconnected() { foreach (var fileinfo in localfileslist) { var task = task.factory.startnew(() => uploadfilesasync(fileinfo)); } } private async task uploadfilesasync(string file) { string remotefilepath = _session.translatelocalpathtoremote(file, @"/", "/test_data_upload"); var uploading = _session.putfiles(file, remotefilepath, false); //when done await task.run(() => thread.sleep(1000)); } } please suggest me correct way. thanks you can use backgroundworker class this: string[] images = new string[50]; foreach (var path in images) { backgroundworker
Read more

aws api gateway - SerializationException in posting new Records via Dynamodb Proxy Service in API -

i getting "__type": "com.amazon.coral.service#serializationexception" as reply in postman & in test console in api gateway trying post record directly dynamodb using api proxy services.. referring aws article - https://aws.amazon.com/blogs/compute/using-amazon-api-gateway-as-a-proxy-for-dynamodb/ here's mapping { "tablename": "tablenamegoeshere", "item": { "id" : "$context.requestid" "eventname" : "$input.path('$.eventname')", "timestamp" : $input.path('$.timestamp'), "answers": "$util.parsejson($input.path('$.answers'))" } } update: did asked ... , worked if try add array of json objects gives me above same error - here's trying now. please - couldnt find on google well #set($inputroot = $input.path('$')) { "tablename": "answer", "item": {
Read more

asp.net - Problems sending emails from forum -

i have been redesigning site has message board, has been written guy looked after site. it has few problems , written in .asp , uses .mdb files database. you can see whole thing here . feel free post if helps, test thing have set using original files , new database. the basic problem when posts message, supposed email sent them, have posted it. when replies, originator supposed message, replier has been posted. i’d have thought @ point in process there should script/file in postmessage.asp? the postmessage.asp page below. <% option explicit %> <!-- #include virtual="common/adovbs.inc" --> <html> <head> <meta http-equiv="content-type" content="text/html; charset=windows-1252"> <meta name="generator" content="microsoft frontpage 4.0"> <meta name="progid" content="frontpage.editor.document"> <title>new page 2</title> <base target="_self"
Read more