org.boon.primitive.Int Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of boon Show documentation
Show all versions of boon Show documentation
Simple opinionated Java for the novice to expert level Java Programmer.
Low Ceremony. High Productivity. A real boon to Java to developers!
/*
* Copyright 2013-2014 Richard M. Hightower
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* __________ _____ __ .__
* \______ \ ____ ____ ____ /\ / \ _____ | | _|__| ____ ____
* | | _// _ \ / _ \ / \ \/ / \ / \\__ \ | |/ / |/ \ / ___\
* | | ( <_> | <_> ) | \ /\ / Y \/ __ \| <| | | \/ /_/ >
* |______ /\____/ \____/|___| / \/ \____|__ (____ /__|_ \__|___| /\___ /
* \/ \/ \/ \/ \/ \//_____/
* ____. ___________ _____ ______________.___.
* | |____ ___ _______ \_ _____/ / _ \ / _____/\__ | |
* | \__ \\ \/ /\__ \ | __)_ / /_\ \ \_____ \ / | |
* /\__| |/ __ \\ / / __ \_ | \/ | \/ \ \____ |
* \________(____ /\_/ (____ / /_______ /\____|__ /_______ / / ______|
* \/ \/ \/ \/ \/ \/
*/
package org.boon.primitive;
import org.boon.Exceptions;
import org.boon.StringScanner;
import org.boon.Universal;
import org.boon.collections.IntList;
import org.boon.core.reflection.BeanUtils;
import org.boon.core.reflection.Invoker;
import org.boon.core.reflection.fields.FieldAccess;
import java.lang.invoke.ConstantCallSite;
import java.lang.invoke.MethodHandle;
import java.lang.reflect.Method;
import java.util.Arrays;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import static org.boon.Exceptions.die;
import static org.boon.Exceptions.handle;
/**
* Integer operations.
*/
public class Int {
/**
* Grown an array
* @param array array of items to grow
* @param size size you would like to grow the array to
* @return the new array
*/
public static int[] grow( int[] array, final int size ) {
int[] newArray = new int[ array.length + size ];
System.arraycopy( array, 0, newArray, 0, array.length );
return newArray;
}
/**
* Double the size of an array.
* @param array the array you are going to double
* @return the new array with the old values copied in
*/
public static int[] grow( int[] array ) {
Exceptions.requireNonNull( array );
int[] newArray = new int[ array.length * 2 ];
System.arraycopy( array, 0, newArray, 0, array.length );
return newArray;
}
/**
* Shrink an array
* @param array the array you want to shrink
* @param size what size do you want the new array
* @return the new array
*/
public static int[] shrink( int[] array, int size ) {
int[] newArray = new int[ array.length - size ];
System.arraycopy( array, 0, newArray, 0, array.length - size );
return newArray;
}
/**
* Takes out all of the 0s
* @param array array to compact
* @return return value
*/
public static int[] compact( int[] array ) {
Exceptions.requireNonNull( array );
int nullCount = 0;
for ( int ch : array ) {
if ( ch == '\0' ) {
nullCount++;
}
}
int[] newArray = new int[ array.length - nullCount ];
int j = 0;
for ( int ch : array ) {
if ( ch == '\0' ) {
continue;
}
newArray[ j ] = ch;
j++;
}
return newArray;
}
/**
* Creates an array of bytes
*
* @param size size of the array you want to make
* @return
*/
public static int[] arrayOfInt( final int size ) {
return new int[ size ];
}
/**
* @param array
* @return
*/
@Universal
public static int[] array( final int... array ) {
Exceptions.requireNonNull( array );
return array;
}
/**
* Returns the lengthOf an array.
* @param array the array you are getting the length from.
* @return array length
*/
@Universal
public static int lengthOf( int[] array ) {
return len(array);
}
/**
* Returns the lengthOf an array.
* @param array the array you are getting the length from.
* @return array length
*/
@Universal
public static int len( int[] array ) {
return array.length;
}
/**
* Returns the value at the given index.
* @param array the array you are getting the from.
* @return the value
*/
@Universal
public static int idx( final int[] array, final int index ) {
final int i = calculateIndex( array, index );
return array[ i ];
}
/**
* Returns the value at the given index.
* @param array the array you are getting the from.
* @return the value
*/
@Universal
public static int atIndex( final int[] array, final int index ) {
final int i = calculateIndex( array, index );
return array[ i ];
}
/**
* Sets the value at the given index.
* @param array the array you are getting the from.
* @return the value
*/
@Universal
public static void idx( final int[] array, int index, int value ) {
final int i = calculateIndex( array, index );
array[ i ] = value;
}
/**
* Sets the value at the given index.
* @param array the array you are setting the value to.
* @param value the new value.
* @return the value
*/
@Universal
public static void atIndex( final int[] array, int index, int value ) {
final int i = calculateIndex( array, index );
array[ i ] = value;
}
/**
* Grabs a slice of this array
* @param array the array you are getting slice from
* @param startIndex the start index of the slice
* @param endIndex the end index of the slice
* @return the new slice
*/
@Universal
public static int[] slc( int[] array, int startIndex, int endIndex ) {
final int start = calculateIndex( array, startIndex );
final int end = calculateEndIndex( array, endIndex );
final int newLength = end - start;
if ( newLength < 0 ) {
throw new ArrayIndexOutOfBoundsException(
String.format( "start index %d, end index %d, length %d",
startIndex, endIndex, array.length )
);
}
int[] newArray = new int[ newLength ];
System.arraycopy( array, start, newArray, 0, newLength );
return newArray;
}
/**
* Grabs a slice of this array
* @param array the array you are getting slice from
* @param startIndex the start index of the slice
* @param endIndex the end index of the slice
* @return the new slice
*/
@Universal
public static int[] sliceOf( int[] array, int startIndex, int endIndex ) {
final int start = calculateIndex( array, startIndex );
final int end = calculateEndIndex( array, endIndex );
final int newLength = end - start;
if ( newLength < 0 ) {
throw new ArrayIndexOutOfBoundsException(
String.format( "start index %d, end index %d, length %d",
startIndex, endIndex, array.length )
);
}
int[] newArray = new int[ newLength ];
System.arraycopy( array, start, newArray, 0, newLength );
return newArray;
}
/**
* Grabs a slice of this array
* @param array the array you are getting slice from
* @param startIndex the start index of the slice
* @return the new slice
*/
@Universal
public static int[] slc( int[] array, int startIndex ) {
final int start = calculateIndex( array, startIndex );
final int newLength = array.length - start;
if ( newLength < 0 ) {
throw new ArrayIndexOutOfBoundsException(
String.format( "start index %d, length %d",
startIndex, array.length )
);
}
int[] newArray = new int[ newLength ];
System.arraycopy( array, start, newArray, 0, newLength );
return newArray;
}
/**
* Grabs a slice of this array
* @param array the array you are getting slice from
* @param startIndex the start index of the slice
* @return the new slice
*/
@Universal
public static int[] sliceOf( int[] array, int startIndex ) {
final int start = calculateIndex( array, startIndex );
final int newLength = array.length - start;
if ( newLength < 0 ) {
throw new ArrayIndexOutOfBoundsException(
String.format( "start index %d, length %d",
startIndex, array.length )
);
}
int[] newArray = new int[ newLength ];
System.arraycopy( array, start, newArray, 0, newLength );
return newArray;
}
/**
* Grabs a slice of this array
* @param array the array you are getting slice from
* @param endIndex the end index of the slice
* @return the new slice
*/
@Universal
public static int[] slcEnd( int[] array, int endIndex ) {
final int end = calculateEndIndex( array, endIndex );
final int newLength = end; // + (endIndex < 0 ? 1 : 0);
if ( newLength < 0 ) {
throw new ArrayIndexOutOfBoundsException(
String.format( "start index %d, length %d",
endIndex, array.length )
);
}
int[] newArray = new int[ newLength ];
System.arraycopy( array, 0, newArray, 0, newLength );
return newArray;
}
/**
* Grabs a slice of this array
* @param array the array you are getting slice from
* @param endIndex the end index of the slice
* @return the new slice
*/
@Universal
public static int[] endSliceOf( int[] array, int endIndex ) {
final int end = calculateEndIndex( array, endIndex );
final int newLength = end; // + (endIndex < 0 ? 1 : 0);
if ( newLength < 0 ) {
throw new ArrayIndexOutOfBoundsException(
String.format( "start index %d, length %d",
endIndex, array.length )
);
}
int[] newArray = new int[ newLength ];
System.arraycopy( array, 0, newArray, 0, newLength );
return newArray;
}
/**
* Checks to see if a value is in the array.
* @param array the array you are getting slice from
* @return true if the value is in the array
*/
@Universal
public static boolean in( int value, int[] array ) {
for ( int currentValue : array ) {
if ( currentValue == value ) {
return true;
}
}
return false;
}
/**
* Copies an array.
* @param array the array you want to copy
* @return the copied array
*/
@Universal
public static int[] copy( int[] array ) {
int[] newArray = new int[ array.length ];
System.arraycopy( array, 0, newArray, 0, array.length );
return newArray;
}
/**
* Adds an int to the array. Grows the array by one and adds the int to the end.
* @param array the array
* @param v the value you are adding to the end.
* @return the new array
*/
@Universal
public static int[] add( int[] array, int v ) {
int[] newArray = new int[ array.length + 1 ];
System.arraycopy( array, 0, newArray, 0, array.length );
newArray[ array.length ] = v;
return newArray;
}
/**
* adds two array together and returns the results.
* @param array first array
* @param array2 second array
* @return
*/
@Universal
public static int[] add( int[] array, int[] array2 ) {
int[] newArray = new int[ array.length + array2.length ];
System.arraycopy( array, 0, newArray, 0, array.length );
System.arraycopy( array2, 0, newArray, array.length, array2.length );
return newArray;
}
/**
* Inserts a value in the midst of another array.
* @param array
* @param idx
* @param v
* @return
*/
@Universal
public static int[] insert( final int[] array, final int idx, final int v ) {
if ( idx >= array.length ) {
return add( array, v );
}
final int index = calculateIndex( array, idx );
//Object newArray = Array.newInstance(array.getClass().getComponentType(), array.length+1);
int[] newArray = new int[ array.length + 1 ];
if ( index != 0 ) {
/* Copy up to the length in the array before the index. */
/* src sbegin dst dbegin length of copy */
System.arraycopy( array, 0, newArray, 0, index );
}
boolean lastIndex = index == array.length - 1;
int remainingIndex = array.length - index;
if ( lastIndex ) {
/* Copy the area after the insert. Make sure we don't write over the end. */
/* src sbegin dst dbegin length of copy */
System.arraycopy( array, index, newArray, index + 1, remainingIndex );
} else {
/* Copy the area after the insert. */
/* src sbegin dst dbegin length of copy */
System.arraycopy( array, index, newArray, index + 1, remainingIndex );
}
newArray[ index ] = v;
return newArray;
}
/**
* Inserts an array in the midst of another array.
* @param array
* @return
*/
@Universal
public static int[] insert( final int[] array, final int fromIndex, final int[] values ) {
if ( fromIndex >= array.length ) {
return add( array, values );
}
final int index = calculateIndex( array, fromIndex );
//Object newArray = Array.newInstance(array.getClass().getComponentType(), array.length+1);
int[] newArray = new int[ array.length + values.length ];
if ( index != 0 ) {
/* Copy up to the length in the array before the index. */
/* src sbegin dst dbegin length of copy */
System.arraycopy( array, 0, newArray, 0, index );
}
boolean lastIndex = index == array.length - 1;
int toIndex = index + values.length;
int remainingIndex = newArray.length - toIndex;
if ( lastIndex ) {
/* Copy the area after the insert. Make sure we don't write over the end. */
/* src sbegin dst dbegin length of copy */
System.arraycopy( array, index, newArray, index + values.length, remainingIndex );
} else {
/* Copy the area after the insert. */
/* src sbegin dst dbegin length of copy */
System.arraycopy( array, index, newArray, index + values.length, remainingIndex );
}
for ( int i = index, j = 0; i < toIndex; i++, j++ ) {
newArray[ i ] = values[ j ];
}
return newArray;
}
/**
* Calculates the index for slice notation so -1 is one minus length and so on.
* @param array array in question
* @param originalIndex the index give which might be negative or higher than length.
* @return
*/
private static int calculateIndex( int[] array, int originalIndex ) {
final int length = array.length;
int index = originalIndex;
/* Adjust for reading from the right as in
-1 reads the 4th element if the length is 5
*/
if ( index < 0 ) {
index = length + index;
}
/* Bounds check
if it is still less than 0, then they
have an negative index that is greater than length
*/
/* Bounds check
if it is still less than 0, then they
have an negative index that is greater than length
*/
if ( index < 0 ) {
index = 0;
}
if ( index >= length ) {
index = length - 1;
}
return index;
}
/**
* Calculates the index for slice notation so -1 is one minus length and so on.
* @param array array in question
* @param originalIndex the index give which might be negative or higher than length.
* @return
*/
private static int calculateEndIndex( int[] array, int originalIndex ) {
final int length = array.length;
int index = originalIndex;
/* Adjust for reading from the right as in
-1 reads the 4th element if the length is 5
*/
if ( index < 0 ) {
index = length + index;
}
/* Bounds check
if it is still less than 0, then they
have an negative index that is greater than length
*/
/* Bounds check
if it is still less than 0, then they
have an negative index that is greater than length
*/
if ( index < 0 ) {
index = 0;
}
if ( index > length ) {
index = length;
}
return index;
}
/** Public interface for a very fast reduce by. */
public static interface ReduceBy {
long reduce(long sum, int value);
}
/**
* A very fast reduce by.
* If performance is your thing, this seems to be as fast a plain for loop when benchmarking with JMH.
*
* @param array array of items to reduce by
* @param reduceBy reduceBy interface
* @return the final value
*/
public static long reduceBy( final int[] array, ReduceBy reduceBy ) {
long sum = 0;
for ( int v : array ) {
sum = reduceBy.reduce(sum, v);
}
return sum;
}
/**
*
* @param array array of items to reduce by
* @param start where to start in the array
* @param length where to end in the array
* @param reduceBy the function to do the reduce by
* @return the reduction
*/
public static long reduceBy( final int[] array, final int start, final int length, ReduceBy reduceBy ) {
long sum = 0;
for (int index = start; index < length; index++) {
int v = array[index];
sum = reduceBy.reduce(sum, v);
}
return sum;
}
/**
*
* @param array array of items to reduce by
* @param length where to end in the array
* @param reduceBy the function to do the reduce by
* @return the reduction
*/
public static long reduceBy( final int[] array, final int length, ReduceBy reduceBy ) {
long sum = 0;
for (int index = 0; index < length; index++) {
int v = array[index];
sum = reduceBy.reduce(sum, v);
}
return sum;
}
/**
* Reduce by functional support for int arrays.
* @param array array of items to reduce by
* @param object object that contains the reduce by function
* @param the type of object
* @return the final reduction
*/
public static long reduceBy( final int[] array, T object ) {
if (object.getClass().isAnonymousClass()) {
return reduceByR(array, object );
}
try {
ConstantCallSite callSite = Invoker.invokeReducerLongIntReturnLongMethodHandle(object);
MethodHandle methodHandle = callSite.dynamicInvoker();
try {
long sum = 0;
for ( int v : array ) {
sum = (long) methodHandle.invokeExact( sum, v );
}
return sum;
} catch (Throwable throwable) {
return handle(Long.class, throwable, "Unable to perform reduceBy");
}
} catch (Exception ex) {
return reduceByR(array, object);
}
}
/**
* Reduce by functional support for int arrays.
* @param array array of items to reduce by
* @param object object that contains the reduce by function
* @param the type of object
* @return the final reduction
*/
public static long reduceBy( final int[] array, T object, String methodName ) {
if (object.getClass().isAnonymousClass()) {
return reduceByR(array, object, methodName);
}
try {
ConstantCallSite callSite = Invoker.invokeReducerLongIntReturnLongMethodHandle(object, methodName);
MethodHandle methodHandle = callSite.dynamicInvoker();
try {
long sum = 0;
for ( int v : array ) {
sum = (long) methodHandle.invokeExact( sum, v );
}
return sum;
} catch (Throwable throwable) {
return handle(Long.class, throwable, "Unable to perform reduceBy");
}
} catch (Exception ex) {
return reduceByR(array, object, methodName);
}
}
/**
* Fallback to reflection if the call-site will not work or did not work
* @param array array of items to reduce by
* @param object function object
* @param type of function object.
* @return
*/
private static long reduceByR( final int[] array, T object ) {
try {
Method method = Invoker.invokeReducerLongIntReturnLongMethod(object);
long sum = 0;
for ( int v : array ) {
sum = (long) method.invoke(object, sum, v);
}
return sum;
} catch (Throwable throwable) {
return handle(Long.class, throwable, "Unable to perform reduceBy");
}
}
/**
* Reflection based reduce by.
* @param array array of items to reduce by
* @param object function
* @param methodName name of method
* @param type of function
* @return reduction
*/
private static long reduceByR( final int[] array, T object, String methodName ) {
try {
Method method = Invoker.invokeReducerLongIntReturnLongMethod(object, methodName);
long sum = 0;
for ( int v : array ) {
sum = (long) method.invoke(object, sum, v);
}
return sum;
} catch (Throwable throwable) {
return handle(Long.class, throwable, "Unable to perform reduceBy");
}
}
/**
* Reflection based reduce by.
* @param array array of items to reduce by
* @param object function
* @param methodName name of method
* @param type of function
* @return reduction
*/
private static long reduceByR( final int[] array, int length, T object, String methodName ) {
try {
Method method = Invoker.invokeReducerLongIntReturnLongMethod(object, methodName);
long sum = 0;
for (int index=0; index< length; index++) {
int v = array[index];
sum = (long) method.invoke(object, sum, v);
}
return sum;
} catch (Throwable throwable) {
return handle(Long.class, throwable, "Unable to perform reduceBy");
}
}
/**
* Reflection based reduce by.
* @param array array of items to reduce by
* @param object function
* @param type of function
* @return reduction
*/
private static long reduceByR( final int[] array, int length, T object ) {
try {
Method method = Invoker.invokeReducerLongIntReturnLongMethod(object);
long sum = 0;
for (int index=0; index< length; index++) {
int v = array[index];
sum = (long) method.invoke(object, sum, v);
}
return sum;
} catch (Throwable throwable) {
return handle(Long.class, throwable, "Unable to perform reduceBy");
}
}
/**
* Reduce By
* @param array array of items to reduce by
* @param length where to end in the array
* @param object function
* @return reduction
*/
public static long reduceBy( final int[] array, int length,
Object object ) {
if (object.getClass().isAnonymousClass()) {
return reduceByR(array, length, object );
}
try {
ConstantCallSite callSite = Invoker.invokeReducerLongIntReturnLongMethodHandle(object );
MethodHandle methodHandle = callSite.dynamicInvoker();
try {
long sum = 0;
for (int index=0; index < length; index++) {
int v = array[index];
sum = (long) methodHandle.invokeExact( sum, v );
}
return sum;
} catch (Throwable throwable) {
return handle(Long.class, throwable, "Unable to perform reduceBy");
}
} catch (Exception ex) {
return reduceByR(array, length, object );
}
}
/**
* Reduce By
* @param array array of items to reduce by
* @param length where to end in the array
* @param function function
* @param function functionName
* @return reduction
*/
public static long reduceBy( final int[] array, int length,
Object function, String functionName ) {
if (function.getClass().isAnonymousClass()) {
return reduceByR(array, length, function, functionName );
}
try {
ConstantCallSite callSite = Invoker.invokeReducerLongIntReturnLongMethodHandle(function, functionName );
MethodHandle methodHandle = callSite.dynamicInvoker();
try {
long sum = 0;
for (int index=0; index < length; index++) {
int v = array[index];
sum = (long) methodHandle.invokeExact( sum, v );
}
return sum;
} catch (Throwable throwable) {
return handle(Long.class, throwable, "Unable to perform reduceBy");
}
} catch (Exception ex) {
return reduceByR(array, length, function, functionName );
}
}
/**
* Reduce By
* @param array array of items to reduce by
* @param length where to end in the array
* @param object function
* @return reduction
*/
public static long reduceBy( final int[] array, int start, int length,
Object object ) {
if (object.getClass().isAnonymousClass()) {
return reduceByR(array, object );
}
try {
ConstantCallSite callSite = Invoker.invokeReducerLongIntReturnLongMethodHandle(object );
MethodHandle methodHandle = callSite.dynamicInvoker();
try {
long sum = 0;
for (int index=start; index < length; index++) {
int v = array[index];
sum = (long) methodHandle.invokeExact( sum, v );
}
return sum;
} catch (Throwable throwable) {
return handle(Long.class, throwable, "Unable to perform reduceBy");
}
} catch (Exception ex) {
return reduceByR(array, object );
}
}
/**
* Checks to see if two values are the same
* @param expected expected value
* @param got got value
* @return true if equal throws exception if not equal
*/
public static boolean equalsOrDie(int expected, int got) {
if (expected != got) {
return die(Boolean.class, "Expected was", expected, "but we got ", got);
}
return true;
}
/**
* Checks to see if two arrays are equals
* @param expected expected array
* @param got got array
* @return true if equal or throws exception if not.
*/
public static boolean equalsOrDie(int[] expected, int[] got) {
if (expected.length != got.length) {
die("Lengths did not match, expected length", expected.length,
"but got", got.length);
}
for (int index=0; index< expected.length; index++) {
if (expected[index]!= got[index]) {
die("value at index did not match index", index , "expected value",
expected[index],
"but got", got[index]);
}
}
return true;
}
/**
* Compares two values
* @param expected expected value
* @param got got value
* @return true or false
*/
public static boolean equals(int expected, int got) {
return expected == got;
}
/**
* Checks to see if two arrays are equals
* @param expected expected array
* @param got got array
* @return true if equal or false if not.
*/
public static boolean equals(int[] expected, int[] got) {
if (expected.length != got.length) {
return false;
}
for (int index=0; index< expected.length; index++) {
if (expected[index]!= got[index]) {
return false;
}
}
return true;
}
/**
* Sum
* Provides overflow protection.
* @param values values in int
* @return sum
*/
public static int sum( int[] values ) {
return sum( values, 0, values.length);
}
/**
* Sum
* Provides overflow protection.
* @param values values in int
* @return sum
*/
public static int sum( int[] values, int length ) {
return sum( values, 0, length);
}
/**
* Sum
* Provides overflow protection.
* @param values values in int
* @return sum
*/
public static int sum( int[] values, int start, int length ) {
long sum = 0;
for (int index = start; index < length; index++ ) {
sum+= values[index];
}
if (sum < Integer.MIN_VALUE) {
die ("overflow the sum is too small", sum);
}
if (sum > Integer.MAX_VALUE) {
die ("overflow the sum is too big", sum);
}
return (int) sum;
}
/**
* Sum
* Provides overflow protection.
* @param values values in int
* @return sum
*/
public static long bigSum( int[] values ) {
return bigSum(values, 0, values.length);
}
/**
* Sum
* Provides overflow protection.
* @param values values in int
* @return sum
*/
public static long bigSum( int[] values, int length ) {
return bigSum(values, 0, length);
}
/**
* Big Sum
* @param values values in int
* @return sum
*/
public static long bigSum( int[] values, int start, int length ) {
long sum = 0;
for (int index = start; index < length; index++ ) {
sum+= values[index];
}
return sum;
}
/**
* Max
* @param values values in int
* @return max
*/
public static int max( int[] values, final int start, final int length ) {
int max = Integer.MIN_VALUE;
for (int index = start; index < length; index++ ) {
if ( values[index] > max ) {
max = values[index];
}
}
return max;
}
/**
* max
* @param values values in int
* @return max
*/
public static int max( int[] values ) {
return max(values, 0, values.length);
}
/**
* max
* @param values values in int
* @return max
*/
public static int max( int[] values, int length ) {
return max(values, 0, length);
}
/**
* Min
* @param values values in int
* @return min
*/
public static int min( int[] values, final int start, final int length ) {
int min = Integer.MAX_VALUE;
for (int index = start; index < length; index++ ) {
if (values[index] < min) min = values[index];
}
return min;
}
/**
* Min
* @param values values in int
* @return min
*/
public static int min( int[] values ) {
return min(values, 0, values.length);
}
/**
* Min
* @param values values in int
* @return min
*/
public static int min( int[] values, int length ) {
return min(values, 0, length);
}
/**
* Average
* @param values values in int
* @return average
*/
public static int mean( int[] values, final int start, final int length ) {
return (int) Math.round(meanDouble(values, start, length));
}
/**
* Average
* @param values values in int
* @return average
*/
public static int mean( int[] values, final int length ) {
return (int) Math.round(meanDouble(values, 0, length));
}
/**
* Average
* @param values values in int
* @return average
*/
public static int mean( int[] values ) {
return (int) Math.round(meanDouble(values, 0, values.length));
}
/**
* Calculate Variance.
*
* @param values values
* @param start start
* @param length length
* @return variance
*/
public static int variance(int[] values, final int start, final int length) {
return (int) Math.round(varianceDouble(values, start, length));
}
private static double meanDouble( int[] values, final int start, final int length ) {
double mean = ((double)bigSum(values, start, length))/ ((double) length);
return mean;
}
/**
* Calculate Variance.
*
* @param values values
* @param start start
* @param length length
* @return variance
*/
public static double varianceDouble(int[] values, final int start, final int length) {
double mean = meanDouble(values, start, length);
double temp = 0;
for(int index = start; index < length; index++) {
double a = values[index];
temp += (mean-a)*(mean-a);
}
return temp / length;
}
/**
* Calculate Variance.
*
* @param values values
* @param length length
* @return variance
*/
public static int variance(int[] values, final int length) {
return (int) Math.round(varianceDouble(values, 0, length));
}
/**
* Calculate Variance.
*
* @param values values
* @return variance
*/
public static int variance(int[] values) {
return (int) Math.round(varianceDouble(values, 0, values.length));
}
/**
* Calculate standard deviation.
*
* @param values values
* @param start start
* @param length length
* @return standard deviation
*/
public static int standardDeviation(int[] values, final int start, final int length) {
double variance = varianceDouble(values, start, length);
return (int)Math.round(Math.sqrt(variance));
}
/**
* Calculate standard deviation.
*
* @param values values
* @param length length
* @return standard deviation
*/
public static int standardDeviation(int[] values, final int length) {
double variance = varianceDouble(values, 0, length);
return (int)Math.round(Math.sqrt(variance));
}
/**
* Calculate standard deviation.
*
* @param values values
* @return standard deviation
*/
public static int standardDeviation(int[] values) {
double variance = varianceDouble(values, 0, values.length);
return (int)Math.round(Math.sqrt(variance));
}
/**
* Calculate Median
*
* @param start start
* @param values values
* @param length length
* @return median
*/
public static int median(int[] values, final int start, final int length) {
int[] sorted = new int[length];
System.arraycopy(values, start, sorted, 0, length);
Arrays.sort(sorted);
if (length % 2 == 0) {
int middle = sorted.length / 2;
double median = (sorted[middle-1] + sorted[middle]) / 2.0;
return (int) Math.round(median);
} else {
return sorted[sorted.length / 2];
}
}
/**
* Calculate Median
* @param values values
* @param length length
* @return median
*/
public static int median(int[] values, final int length) {
return median(values, 0, length);
}
/**
* Calculate Median
* @param values values
* @return median
*/
public static int median(int[] values) {
return median(values, 0, values.length);
}
/**
* Checks to see if two arrays are equals
* @param expected expected array
* @param got got array
* @return true if equal or false if not.
*/
public static boolean equals(int start, int end, int[] expected, int[] got) {
if (expected.length != got.length) {
return false;
}
for (int index=start; index< end; index++) {
if (expected[index]!= got[index]) {
return false;
}
}
return true;
}
public static int hashCode(int array[]) {
if (array == null)
return 0;
int result = 1;
for (int element : array) {
result = 31 * result + element;
}
return result;
}
public static int hashCode(int start, int end, int array[]) {
if (array == null)
return 0;
int result = 1;
for (int index=start; index< end; index++) {
result = 31 * result + array[index];
}
return result;
}
/**
* Calculate a sum of a property from a list.
* @param inputList
* @param propertyPath to item we want to sum
* @return sum
*/
public static long sum( Collection inputList, String propertyPath ) {
if (inputList.size() == 0 ) {
return 0;
}
long sum = 0l;
if (propertyPath.contains(".") || propertyPath.contains("[")) {
String[] properties = StringScanner.splitByDelimiters(propertyPath, ".[]");
for (Object o : inputList) {
sum+=BeanUtils.getPropertyInt(o, properties);
}
} else {
Map fields = BeanUtils.getFieldsFromObject(inputList.iterator().next());
FieldAccess fieldAccess = fields.get(propertyPath);
for (Object o : inputList) {
sum += fieldAccess.getInt(o);
}
}
return sum;
}
private static double mean( Collection inputList, String propertyPath ) {
double mean = sum(inputList, propertyPath)/inputList.size();
return Math.round(mean);
}
public static double variance(Collection inputList, String propertyPath) {
double mean = mean(inputList, propertyPath);
double temp = 0;
double a;
if (propertyPath.contains(".") || propertyPath.contains("[")) {
String[] properties = StringScanner.splitByDelimiters(propertyPath, ".[]");
for (Object o : inputList) {
a =BeanUtils.getPropertyInt(o, properties);
temp += (mean-a)*(mean-a);
}
} else {
Map fields = BeanUtils.getFieldsFromObject(inputList.iterator().next());
FieldAccess fieldAccess = fields.get(propertyPath);
for (Object o : inputList) {
a = fieldAccess.getInt(o);
temp += (mean-a)*(mean-a);
}
}
return Math.round(temp / inputList.size());
}
/**
* Calculate standard deviation.
*
* @return standard deviation
*/
public static double standardDeviation(Collection inputList, String propertyPath) {
double variance = variance(inputList, propertyPath);
return Math.round(Math.sqrt(variance));
}
/**
* Calculate standard deviation.
*
* @return standard deviation
*/
public static int median(Collection inputList, String propertyPath) {
return IntList.toIntList(inputList, propertyPath).median();
}
/**
* Round up to the nearest power of 2
* @param number number you want to round up to.
* @return rounded up to the power of 2.
*/
public static int roundUpToPowerOf2( int number ) {
int rounded = number >= 1_000
? 1_000
: ( rounded = Integer.highestOneBit( number ) ) != 0
? ( Integer.bitCount( number ) > 1 ) ? rounded << 1 : rounded
: 1;
return rounded;
}
}