cluster-computing

问题 I know that Cassandra have different read consistency levels but I haven't seen a consistency level which allows as read data by key only from one node. I mean if we have a cluster with a replication factor of 3 then we will always ask all nodes when we read. Even if we choose a consistency level of one we will ask all nodes but wait for the first response from any node. That is why we will load not only one node when we read but 3 (4 with a coordinator node). I think we can't really improve

问题 How I do a general function to insert the colors of the clusters? I used the leaflet package to generate the map. The way I did it was "if else", it worked, but if for example, I have 15 clusters, I will have many "if else". Can anybody help me ?? In addition, if possible I would like to put legend of the clusters on my map as well. My executable code is below: library(leaflet) library(geosphere) #database df<-structure(list(Properties = c(1,2,3,4,5,6,7,8,9,10), Latitude = c(-23.2, -23.6, -23

问题 I was wondering about how to set up a h2o cluster using multiple AWS EC2 instances and R-Studio. I am not a computer scientist, so sorry for the trivial questions (!) Based on this tutorial (http://amunategui.github.io/h2o-on-aws/) I sucessfully installed h2o and R-Studio on an AWS EC2 instance (Linux). But I rather want to create a multi-instance cluster with lets say 4 instance with 8 cores each. Following this (http://h2o-release.s3.amazonaws.com/h2o/rel-lambert/5/docs-website/deployment

问题 I have bellow python code to build knn graph but I have an error: AttributeError: 'Graph' object has no attribute 'node'. It seems that the nx.Graph() has no node attribute but I don't know what should I replace with that. import networkx as nx def knn_graph(df, k, verbose=False): points = [p[1:] for p in df.itertuples()] g = nx.Graph() if verbose: print ("Building kNN graph (k = %d)" % (k)) iterpoints = tqdm(enumerate(points), total=len(points)) if verbose else enumerate(points) for i, p in

问题 I have bellow python code to build knn graph but I have an error: AttributeError: 'Graph' object has no attribute 'node'. It seems that the nx.Graph() has no node attribute but I don't know what should I replace with that. import networkx as nx def knn_graph(df, k, verbose=False): points = [p[1:] for p in df.itertuples()] g = nx.Graph() if verbose: print ("Building kNN graph (k = %d)" % (k)) iterpoints = tqdm(enumerate(points), total=len(points)) if verbose else enumerate(points) for i, p in

问题 I have bellow python code to build knn graph but I have an error: AttributeError: 'Graph' object has no attribute 'node'. It seems that the nx.Graph() has no node attribute but I don't know what should I replace with that. import networkx as nx def knn_graph(df, k, verbose=False): points = [p[1:] for p in df.itertuples()] g = nx.Graph() if verbose: print ("Building kNN graph (k = %d)" % (k)) iterpoints = tqdm(enumerate(points), total=len(points)) if verbose else enumerate(points) for i, p in

问题 I read how current master election algorithms like Raft, Paxos or Zab elect master on a cluster and couldn't understand why they use sophisticated algorithms instead of simple bully algorithm. I'm developing a cluster library and use UDP Multicast for heartbeat messages. Each node joins a multicast address and also send datagram packets periodically to that address. If the nodes find out there is a new node that sends packets to this multicast address, the node is simply added to cluster and

问题 In WordCloud on Python I would like to merge two languages ​​into one picture (English, Arabic) but I was unable to add the Arabic language as you see a squares instead of words and when I call the Arabic_reshaper library and make it read the csv file It shows me the Arabic language and make the English language as a squares wordcloud = WordCloud( collocations = False, width=1600, height=800, background_color='white', stopwords=stopwords, max_words=150, random_state=42, #font_path='/Users/mac

问题 We are trying to start our app with pm2 0.12.8 on ubuntu 14.04 with octa core proccessor. The read me on the git hub has a very straight forward command for running node app in cluster mode. # Cluster mode $ pm2 start app.js -i 0 **# Will start maximum processes with LB depending on available CPUs** $ pm2 start app.js -i max **# Same as above, but deprecated yet.** But the above command are not working for us. When we try to run these commands only one instance is listed by pm2. Why? Any

问题 I would like R to run a script anytime I start up R. I am using R on a Linux cluster and I do not have access to R installation and the .Rprofile file and I cannot find it either. I can run R and have my local packages/libraries. For example, I would like to set the lib paths each time R is started. .libPaths("path") Is it possible to define and set a path for a custom startup script file? In a non-interactive session, I could do in Bash something like Rscript script.R and my script.R has