Questions tagged [combiners]
105 questions
1
vote
3 answers
C# How Combine Some Linq Expression In a Loop
i want to combine some Linq Expression, so i help from below articles:
http://www.c-sharpcorner.com/uploadfile/04fe4a/predicate-combinators-in-linq/
and
http://thanhhh.blogspot.com/2011/10/linq-to-entities-predicatebuilder-and.html
and i have a…
Mahdi Radi
- 429
- 2
- 10
- 30
1
vote
1 answer
Combination of a matrix of arrays of variable length
I have to obtain all possibile combination of this kind of matrix:
String[][] matrix = {
{"AA-123", "AA-124", "AA-125", "AA-126"},
{"BB-12", "BB-13"},
{"CC-1"},
};
After all, that is the final implementation. It's in Java, but the language…
Yohji
- 170
- 8
1
vote
2 answers
C# fast img merging
Today I wanted to try sth new in image processing in C#.
Szenario as following: I have two black and white images. Now I want to get all white pixels (x,y) from both images and put them into a return image. So in the end my image3 contains all white…
user3079834
- 2,009
- 2
- 31
- 63
1
vote
1 answer
HADOOP combiner operation functioning
I have a doubt about combiner functioning in Hadoop Map/Reduce Framework. The combiner operation is applied only on key-value pairs output by a map task or on all map tasks occurring on a given node.
In fact, i have done some tests and it seems to…
SlimShady
- 43
- 8
1
vote
2 answers
Does combiner runs conditionally
min.num.spills.for.combine (default 3)
What does it signify?
a) The min no. of a map spills to have for a combiner to run? So even though we have specified a combiner, its not guaranteed to run?
b) The min no. of spills to have before the…
S Kr
- 1,831
- 2
- 25
- 50
1
vote
1 answer
Is there a combiner phase in Mongo DB's map reduce framework
Is there any thing similar to Combiner (as in Hadoop Map Reduce) in Mongo DB's map reduce framework. We're trying out the map reduce framework in Mongo DB cluster, and there are several rows for a key which could potentially be combined before being…
Ouroboros
- 1,432
- 1
- 19
- 41
1
vote
0 answers
Map-Reduce combiner does not work
I have tried to use this script:
http://www.cs.bgu.ac.il/~dsp112/Map-Reduce_Template
But the Combiner fails at (line 69).
Combine output records 11,746,934
...
Combine input records 11,746,934
I have analysed the text flat file, but how I can…
Kukuruka
- 209
- 1
- 9
- 13
0
votes
1 answer
Is it possible to add a "Combine" step to the Amazon Elastic MapReduce workflow?
I am referring to the Combine step mentioned on the Hadoop wiki. I have been unable to find a reference to it in the AWS documentation, and I'd like to utilize this step.
Josh Diehl
- 2,913
- 2
- 31
- 43
0
votes
0 answers
Does mapreduce fetch entire map-combiner output before starting reducer or does it make many partial progresses?
I am confused with the following two conflicting notions about mapreduce both arising from the same source:
Is it:
reducer side fetches the entire output of (map-combine)er, sorts and then applies the reduce function in one shot. I get this notion…
figs_and_nuts
- 4,870
- 2
- 31
- 56
0
votes
0 answers
mapreduce : what is the expected output from the combiner
I have read that the combiner reduces the network traffic between mappers and reducers. It is kind of like a semi-reducer which summarises the results before they are sent across the network to the reducers.
However, I am not able to understand the…
figs_and_nuts
- 4,870
- 2
- 31
- 56
0
votes
1 answer
How combiner works when we use multiple inputs in Hadoop MapReduce
I am implementing reduce side Join in Hadoop MapReduce(Java) for that purpose I am using multiple inputs, e.g there are two files Customers and Orders and I joined them considering cid(customer_id).
My Questions :
In the above program if I write…
Sandeep Patil
- 21
- 4
0
votes
3 answers
Combine 2 csv file using python with the specified amount
I want to combine 2 file CSV data, but not all data.
e.g:
a.csv + b.csv, where b.csv have 20 data. But I want to take only 10 data from that, and then take 11-20 data. Or the first 10 and the second 10
Then insert the first 10 data into a.csv, and…
Trya Sovi Kartikasari
- 81
- 1
- 1
- 7
0
votes
0 answers
How to Join Wav files in One Using C#
I create a software to concatenate wav files into one
I use this code
using Alvas.Audio;
private void JoinWav()
{
string[] files = new string[] { "file01_01.wav","file01_01.wav"};
AudioCompressionManager.Join("res.wav", files);
}
It's…
Milad Mokhtari
- 35
- 1
- 5
0
votes
2 answers
PHP Merge two arrays to combine to get expected o/p
I have an array with values
[{
"id": "17",
"pf_label": "Gender"
},
{
"id": "18",
"pf_label": "Age"
},
{
"id": "12",
"pf_label": "Address Line"
}
]
and i have another array
[{
…
Kiran JB
- 1
- 3
0
votes
1 answer
Combining two arrays in python term by term
long =np.array(data.Longitude)
lat = np.array(data.Latitude)
coordinates = np.array(385)
for i in range(385):
coordinates[i] = np.array([lat[i], long[i]])
#x, y = kmeans2(whiten(coordinates), 3, iter = 20)
#plt.scatter(coordinates[:,0],…
Pankaj
- 55
- 1
- 8