Difference between revisions of "Slices"

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{{warning | Do NOT Copy The Data Into SubArrays}}
 
{{warning | Do NOT Copy The Data Into SubArrays}}
  
=Background=
+
=class Slice<T>=
 
 
As the name suggests, we will create a class to represent a <code>Slice</code> of data and a list of <code>Slice</code> called <code>Slices</code> which divides the data into a specified number of <code>Slice</code> given an array of data.
 
 
 
=Where to Start=
 
 
 
Navigate to the slice directory and look under <code>slice.studio</code>. You must implement <code>Slices</code> using the implementation of <code>Slice</code> given to you under the <code>slice.core</code> directory.
 
 
 
==createNSlices==
 
 
 
To create this slice, you will start at the beginning of the data array and keep creating new slices until you have numSlices which more or less evenly span the range. Remember that the sliceId should start at the zero index and the length of the list should be equal to the number of slices. Also remember that if the range is not divisible by numSlices, you must account for this by either evenly distributing the extras or making a slightly larger slice at the end of the range.
 
 
 
 
Hint: you do not need to divide up the array of data fed into the method and doing so would remove the need for a <code>minInclusive</code> variable for a <code>Slice</code>.
 
Hint: you do not need to divide up the array of data fed into the method and doing so would remove the need for a <code>minInclusive</code> variable for a <code>Slice</code>.
 +
==getOriginalUnslicedData()==
 +
==getSliceIndexId()==
 +
==getMinInclusive()==
 +
==getMaxExclusive()==
  
 
=Javadocs=
 
=Javadocs=

Revision as of 04:17, 22 January 2018

Motivation

Coarsening, or n-way split as we tend to call it in this course, comes up a fair amount. This studio has you implement a utility that you can use over and over throughout the semester.

In order to support future testing well, we are strict about exactly how the data is split up among the slices.

Code to Implement

class: Slices.java Java.png
methods: createNSlicesForArrayObject
package: slices.studio
source folder: student/src/main/java

createNSlicesForArrayObject

In order to support primitive arrays (e.g. byte[], int[], et cetera) and non-primitive arrays (e.g. Object[]) we provide all of the public methods, each which simply call the single method requiring implementation:

method: createNSlicesForArrayObject Sequential.svg (sequential implementation only)

	public static <T> List<Slice<T[]>> createNSlices(T[] data, int numSlices) {
		return createNSlicesForArrayObject(data, numSlices);
	}
	public static List<Slice<byte[]>> createNSlices(byte[] data, int numSlices) {
		return createNSlicesForArrayObject(data, numSlices);
	}
	public static List<Slice<char[]>> createNSlices(char[] data, int numSlices) {
		return createNSlicesForArrayObject(data, numSlices);
	}
	public static List<Slice<short[]>> createNSlices(short[] data, int numSlices) {
		return createNSlicesForArrayObject(data, numSlices);
	}
	public static List<Slice<int[]>> createNSlices(int[] data, int numSlices) {
		return createNSlicesForArrayObject(data, numSlices);
	}
	public static List<Slice<long[]>> createNSlices(long[] data, int numSlices) {
		return createNSlicesForArrayObject(data, numSlices);
	}
	public static List<Slice<float[]>> createNSlices(float[] data, int numSlices) {
		return createNSlicesForArrayObject(data, numSlices);
	}
	public static List<Slice<double[]>> createNSlices(double[] data, int numSlices) {
		return createNSlicesForArrayObject(data, numSlices);
	}

To pull this off we will need to use the Array.getLength(Object) method.

Strict Specification

We are overly strict about the specification of how the data must be sliced up. This is to allow to accurately compare results intermediate results throughout the semester.

Example: array.length=7; numSlices=4

Distribute the remainder 1 each to the lower end slices.

A A B B C C D
Attention niels epting.svg Warning:Do NOT slice up the data by giving all of the remainder to one slice

A |B |C |D |D |D |D

Mistakes To Avoid

Attention niels epting.svg Warning: Do NOT Parallelize
Attention niels epting.svg Warning: Do NOT Copy The Data Into SubArrays

class Slice<T>

Hint: you do not need to divide up the array of data fed into the method and doing so would remove the need for a minInclusive variable for a Slice.

getOriginalUnslicedData()

getSliceIndexId()

getMinInclusive()

getMaxExclusive()

Javadocs

use: class Slice

Testing Your Solution

Correctness

class: SlicesTestSuite.java Junit.png
package: slice.studio
source folder: testing/src/test/java