large-data

This question already has an answer here: file_get_contents => PHP Fatal error: Allowed memory exhausted 3 answers I am reading csv & checking with mysql that records are present in my table or not in php. csv has near about 25000 records & when i run my code it display "Service Unavailable" error after 2m 10s (onload: 2m 10s) here i have added code // for set memory limit & execution time ini_set('memory_limit', '512M'); ini_set('max_execution_time', '180'); //function to read csv file function readCSV($csvFile) { $file_handle = fopen($csvFile, 'r'); while (!feof($file_handle) ) { set_time

I am trying to read a large csv file into R. I only want to read and work with some of the rows that fulfil a particular condition (e.g. Variable2 >= 3 ). This is a much smaller dataset. I want to read these lines directly into a dataframe, rather than load the whole dataset into a dataframe and then select according to the condition, since the whole dataset does not easily fit into memory. You could use the read.csv.sql function in the sqldf package and filter using SQL select. From the help page of read.csv.sql : library(sqldf) write.csv(iris, "iris.csv", quote = FALSE, row.names = FALSE)

This question already has an answer here: Overlay data onto background image 3 answers I made a plot with a 3 million points and saved it as PNG. It took a few hours and I would like to avoid re-drawing all the points. How can I generate a new plot that has this PNG as a background? Try this: library(png) #Replace the directory and file information with your info ima <- readPNG("C:\\Documents and Settings\\Bill\\Data\\R\\Data\\Images\\sun.png") #Set up the plot area plot(1:2, type='n', main="Plotting Over an Image", xlab="x", ylab="y") #Get the plot information so the image will fill the plot

I am implementing Kosaraju's Strong Connected Component(SCC) graph search algorithm in Python. The program runs great on small data set, but when I run it on a super-large graph (more than 800,000 nodes), it says "Segmentation Fault". What might be the cause of it? Thank you! Additional Info: First I got this Error when running on the super-large data set: "RuntimeError: maximum recursion depth exceeded in cmp" Then I reset the recursion limit using sys.setrecursionlimit(50000) but got a 'Segmentation fault' Believe me it's not a infinite loop, it runs correct on relatively smaller data. It is

I am trying to migrate a database where images were stored in the database to a record in the database pointing at a file on the hard drive. I was trying to use Parallel.ForEach to speed up the process using this method to query out the data. However, I noticed that I was getting an OutOfMemory Exception. I know Parallel.ForEach will query a batch of enumerables to mitigate the cost of overhead if there is one for spacing the queries out (so your source will more likely have the next record cached in memory if you do a bunch of queries at once instead of spacing them out). The issue is due to