Change the implementation of ArrayUtils.range to include the stop value if it is a multiple of step.

This commit is contained in:
Kevin Ruland 2012-08-10 20:03:21 +00:00
parent ead406e852
commit 43b269c0f4
2 changed files with 13 additions and 10 deletions

View File

@ -6,16 +6,11 @@ public class ArrayUtils {
/**
* Returns a double array with values from start to end with given step.
* Starts exactly at start and stops at the step before stop is reached.
* Starts exactly at start and stops at the multiple of step <= stop.
*/
public static double[] range(double start, double stop, double step){
int size = 0 ;
if ( stop <= start ) {
size = 0;
} else {
size = (int) Math.ceil(((stop - start) / step));
}
int size = (int) Math.floor(((stop - start) / step)) + 1;
//System.out.println("Range from "+start+" to "+stop+" step "+step+" has length "+size);

View File

@ -80,6 +80,13 @@ public class ArrayUtilsTest {
}
@Test
public void testRante0() {
double[] ary = ArrayUtils.range(0., 0., 1.0);
assertEquals(1, ary.length);
assertEquals( 0.0, ary[0], 0.0 );
}
@Test
public void testRange1() {
double[] ary = ArrayUtils.range(0.0, 0.5, 1.0);
@ -90,9 +97,10 @@ public class ArrayUtilsTest {
@Test
public void testRange2() {
double[] ary = ArrayUtils.range(0.0, 1.0, 0.5);
assertEquals(2, ary.length);
assertEquals(3, ary.length);
assertEquals( 0.0, ary[0], 0.0 );
assertEquals( 0.5, ary[1], 0.0 );
assertEquals( 1.0, ary[2], 0.0 );
}
@Test
@ -107,9 +115,9 @@ public class ArrayUtilsTest {
@Test
public void testRange4() {
double[] ary = ArrayUtils.range(0.0,10.0, 0.5);
assertEquals( 20, ary.length );
assertEquals( 21, ary.length );
int i =0;
for( double d = 0.0; d < 10.0; d+=0.5){
for( double d = 0.0; d < 10.2; d+=0.5){
assertEquals(d,ary[i++],0.0);
}
assertEquals( i, ary.length );