Questions tagged [parallel-foreach]
this is a library in R which allows for easy parallel processing
parallel-foreach
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R foreach does not improve speed
I am trying to use foreach to parallelize some matrix calculations. However, I found it gives similar performance to apply and for loop, despite I used 10 cores.
library(microbenchmark)
library(...
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2
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58
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Using timeout and parallel in operations with DB
I have implemented a code that does several operations on the DB. Now I have decided to parallelize it to improve performance. To do this I have changed all asynchronous operations to synchronous, and ...
- 2,417
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R crashes with segfault in doing keras::unserialize_model() in foreach loop from doParallel
I'm having a problem where R crashes when calling keras::unserialize_model() in a doParallel foreach loop.
I have to sanitize this code, so hopefully I don't munge anything. And I'm not an R developer;...
- 1,528
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sf_distance within for within for each parallelisation
Overall, I have a data frame with buildings with a spatial variable connected. Then I have another file of e.g. forests, similarly
Total_df:
Id
Variables
SFC Point object
Zip codes
1
10
POINT (...
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2
answers
100
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StopIteration error in nested foreach/for loop
I've got a nasty error which only shows up when you ask R with geterrmessage() to actually display it. It also is no problem as long as you run the code in an interactive console session but when you ...
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foreach gives the expected output only if I put a print statement at the end of the loop
I am using foreach to parallelize my code. However, I found the result to be different whether I add print statement at the end of the loop or not.
Here is with the print statement a the end (I get ...
- 3,304
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2
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75
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Parallel.ForEarch - iterating through files in folders/subfolders, some files are missing/skipped
Trying to get the CRC32 of all files in folder/subfolders and write the result in a simple text box, but in the process some files are skipped using the *Parallel.ForEach *loop.
The code:
Imports ...
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2
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1
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54
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do.call() function within %do.par%, function arguments not found
I am implementing a Monte Carlo simulation to test several methods (many of them).
The methods are implementented in a methods.R script. To illustrate, let's say that I have only implemented 2 methods....
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1
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91
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C# Parallel.ForEach throw IndexOutOfBounds but foreach does not?
My program must check the state of all elements in array. When I use foreach it's ok, but in Parallel.ForEach and Parallel.For it throws index out of bounds exception.
This code works:
foreach (var p ...
- 21
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can we modify an empty environment variable inside a parralled foreach?
I want to first pass an empty environment variable to a paralleled foreach in R
and then modify the empty environment variable inside the paralleled foreach.
I want the empty environment variable to ...
- 21
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Is it possible use foreach in parallel for all nests for a function using input from previous step in R?
I am running some heavy simulations in R. Hence, I have been trying to parallelize my computations to speed it up. I have figured out how to use the foreach package to run a loop in parallel. I have ...
- 55
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1
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80
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Shared library is not recognized when using parallel foreach in R
I am using a shared library written in C in my R code. I load the compiled shared library using dyn.load command. I am going to call a shared library function in a parallelized foreach loop. Here is ...
- 329
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2
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116
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Does not save file using foreach loop in R
I am encountering difficulties saving data related to "abc" into a file named "myResults.rds". My code is complex and involves multiple operations within a foreach loop. I wish to ...
- 89
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%dopar% is very slow when using iterators compared to loading the data from text file
%dopar% is phenomenally slower when using iterators, compared to loading the data from text file.
I've compared 3 use cases
using %dopar% without any iterators dopar1
using %dopar% with iterators ...
- 97
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1
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246
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Cancellation token in Parallel.ForEach loop not working
I can't seem to stop the Parallel.ForEach tasks below on CTRL-C, am I not catching the exceptions correctly? I have a long running operation in a while loop.
Can anyone tell me what I'm not doing ...
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