apache spark - How to open a file which is stored in HDFS in pySpark using with open -


how open file stored in hdfs - here input file hdfs - if give file bellow , wont able open , show file not found

from pyspark import sparkconf,sparkcontext conf = sparkconf () sc = sparkcontext(conf = conf) def getmoviename():     movienames = {}     open ("/user/sachinkerala6174/indata/moviestat") f:         line in f:             fields = line.split("|")             mid = fields[0]             mname = fields[1]             movienames[int(fields[0])] = fields[1]             return movienames namedict = sc.broadcast(getmoviename())

my assumption use 

with open (sc.textfile("/user/sachinkerala6174/indata/moviestat")) f:

but didnt work

to read textfile rdd:

rdd_name = sc.textfile("/user/sachinkerala6174/indata/moviestat")

you can use "collect()" in order use in pure python (not recommended - use on small data), or use spark rdd methods in order manipulate using pyspark methods (the recommended way)

for more info: http://spark.apache.org/docs/2.0.1/api/python/pyspark.html

textfile(name, minpartitions=none, use_unicode=true)

read text file hdfs, local file system (available on nodes), or hadoop-supported file system uri, , return rdd of strings.

if use_unicode false, strings kept str (encoding utf-8), faster , smaller unicode. (added in spark 1.2)

>>> path = os.path.join(tempdir, "sample-text.txt") >>> open(path, "w") testfile: ...    _ = testfile.write("hello world!") >>> textfile = sc.textfile(path) >>> textfile.collect() [u'hello world!']

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