Getting a sequence of indexes
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0
I'm having a bit of a problem. The assignment is to take a picture, run it through an EdgeDetector, and get a 3 axis matrixprinter to draw the edge.
Most of it I got covered, but one major obstacle remains. When I run my picture through my Sobel and use a binary truncate it returns a 2D int array of 0's and 255's. Just an example of a test array for better understanding.
255 255 255 255 255 255 255 255
255 0 0 0 255 0 0 255
255 255 0 0 0 255 255 255
255 0 0 255 255 0 0 255
255 255 255 0 255 0 0 255
255 0 255 0 0 0 0 255
255 255 255 255 255 255 255 255
I'm then using a nested for loop to go through the array and give me an i coordinate, j coordinate and magnitude for each position in the array, like this. I'm using the StringBuilder, because I need to send a String to the PLC.
public static void stringBuilder(int m)
// start method stringbuilder
StringBuilder sb = new StringBuilder();
for (int i = 0 ; i < m.length ; i++)
// start i for loop
for ( int j = 0 ; j < m[i].length ; j++)
// start j for loop
int magnitude = m[j][i];
/*
sb.append("(");
sb.append(i);
sb.append(",");
sb.append(j);
sb.append(")");
sb.append(" : ");
*/
if (magnitude == 0)
sb.append(magnitude);
sb.append(" ");
else
sb.append(magnitude);
sb.append(" ");
sb.append(" ");
// end j for loop
sb.append("n");
// end i for loop
System.out.println(sb);
// end method stringbuilder
I have also figured out how to print the elements of connected elements like this. This is by row, but have methods by column, diagonaly left and right. Again putting it in a StringBuilder.
for (int i = 0; i < n.length ; i++)
{
for (int j = 0; j < n[0].length ; j++)
int d = j + 1;
int e = j - 1;
if (d < n[0].length)
Now here's the problem. I would very much like to be able to send a string to the PLC containing only the coordinates where it is suppose to draw. In the example array I would be:
0,0 to 0,7 up
1,0 up; 1,1 to 1,3 down; 1,4 up; 1,5 to 1,6 down; 1,7 up
2,0 to 2,1 up ; 2,2 to 2,4 down ; 2,5 to 2,7 up
3,0 up ; 3,1 to 3,2 down ; 3,3 to 3,4 up ; 3,5 to 3,6 down ; 3,7 up
and so on and so forth.
In essence getting a sequense of element in the middle of the array.
The idea behind this is that the differens in j coordinates can be translated to a number of steps in a steppermotor.
I just can't figure out how to do it.
java arrays multidimensional-array
edited Nov 15 '18 at 9:20
Andrea
4,54012144
asked Nov 15 '18 at 7:57
Peter Lindhøj TuxenPeter Lindhøj Tuxen
102
add a comment |
0
I'm having a bit of a problem. The assignment is to take a picture, run it through an EdgeDetector, and get a 3 axis matrixprinter to draw the edge.
Most of it I got covered, but one major obstacle remains. When I run my picture through my Sobel and use a binary truncate it returns a 2D int array of 0's and 255's. Just an example of a test array for better understanding.
255 255 255 255 255 255 255 255
255 0 0 0 255 0 0 255
255 255 0 0 0 255 255 255
255 0 0 255 255 0 0 255
255 255 255 0 255 0 0 255
255 0 255 0 0 0 0 255
255 255 255 255 255 255 255 255
I'm then using a nested for loop to go through the array and give me an i coordinate, j coordinate and magnitude for each position in the array, like this. I'm using the StringBuilder, because I need to send a String to the PLC.
public static void stringBuilder(int m)
// start method stringbuilder
StringBuilder sb = new StringBuilder();
for (int i = 0 ; i < m.length ; i++)
// start i for loop
for ( int j = 0 ; j < m[i].length ; j++)
// start j for loop
int magnitude = m[j][i];
/*
sb.append("(");
sb.append(i);
sb.append(",");
sb.append(j);
sb.append(")");
sb.append(" : ");
*/
if (magnitude == 0)
sb.append(magnitude);
sb.append(" ");
else
sb.append(magnitude);
sb.append(" ");
sb.append(" ");
// end j for loop
sb.append("n");
// end i for loop
System.out.println(sb);
// end method stringbuilder
I have also figured out how to print the elements of connected elements like this. This is by row, but have methods by column, diagonaly left and right. Again putting it in a StringBuilder.
for (int i = 0; i < n.length ; i++)
{
for (int j = 0; j < n[0].length ; j++)
int d = j + 1;
int e = j - 1;
if (d < n[0].length)
Now here's the problem. I would very much like to be able to send a string to the PLC containing only the coordinates where it is suppose to draw. In the example array I would be:
0,0 to 0,7 up
1,0 up; 1,1 to 1,3 down; 1,4 up; 1,5 to 1,6 down; 1,7 up
2,0 to 2,1 up ; 2,2 to 2,4 down ; 2,5 to 2,7 up
3,0 up ; 3,1 to 3,2 down ; 3,3 to 3,4 up ; 3,5 to 3,6 down ; 3,7 up
and so on and so forth.
In essence getting a sequense of element in the middle of the array.
The idea behind this is that the differens in j coordinates can be translated to a number of steps in a steppermotor.
I just can't figure out how to do it.
java arrays multidimensional-array
edited Nov 15 '18 at 9:20
Andrea
4,54012144
asked Nov 15 '18 at 7:57
Peter Lindhøj TuxenPeter Lindhøj Tuxen
102
add a comment |
0
0
0
I'm having a bit of a problem. The assignment is to take a picture, run it through an EdgeDetector, and get a 3 axis matrixprinter to draw the edge.
Most of it I got covered, but one major obstacle remains. When I run my picture through my Sobel and use a binary truncate it returns a 2D int array of 0's and 255's. Just an example of a test array for better understanding.
255 255 255 255 255 255 255 255
255 0 0 0 255 0 0 255
255 255 0 0 0 255 255 255
255 0 0 255 255 0 0 255
255 255 255 0 255 0 0 255
255 0 255 0 0 0 0 255
255 255 255 255 255 255 255 255
I'm then using a nested for loop to go through the array and give me an i coordinate, j coordinate and magnitude for each position in the array, like this. I'm using the StringBuilder, because I need to send a String to the PLC.
public static void stringBuilder(int m)
// start method stringbuilder
StringBuilder sb = new StringBuilder();
for (int i = 0 ; i < m.length ; i++)
// start i for loop
for ( int j = 0 ; j < m[i].length ; j++)
// start j for loop
int magnitude = m[j][i];
/*
sb.append("(");
sb.append(i);
sb.append(",");
sb.append(j);
sb.append(")");
sb.append(" : ");
*/
if (magnitude == 0)
sb.append(magnitude);
sb.append(" ");
else
sb.append(magnitude);
sb.append(" ");
sb.append(" ");
// end j for loop
sb.append("n");
// end i for loop
System.out.println(sb);
// end method stringbuilder
I have also figured out how to print the elements of connected elements like this. This is by row, but have methods by column, diagonaly left and right. Again putting it in a StringBuilder.
for (int i = 0; i < n.length ; i++)
{
for (int j = 0; j < n[0].length ; j++)
int d = j + 1;
int e = j - 1;
if (d < n[0].length)
Now here's the problem. I would very much like to be able to send a string to the PLC containing only the coordinates where it is suppose to draw. In the example array I would be:
0,0 to 0,7 up
1,0 up; 1,1 to 1,3 down; 1,4 up; 1,5 to 1,6 down; 1,7 up
2,0 to 2,1 up ; 2,2 to 2,4 down ; 2,5 to 2,7 up
3,0 up ; 3,1 to 3,2 down ; 3,3 to 3,4 up ; 3,5 to 3,6 down ; 3,7 up
and so on and so forth.
In essence getting a sequense of element in the middle of the array.
The idea behind this is that the differens in j coordinates can be translated to a number of steps in a steppermotor.
I just can't figure out how to do it.
java arrays multidimensional-array
edited Nov 15 '18 at 9:20
Andrea
4,54012144
asked Nov 15 '18 at 7:57
Peter Lindhøj TuxenPeter Lindhøj Tuxen
102
I'm having a bit of a problem. The assignment is to take a picture, run it through an EdgeDetector, and get a 3 axis matrixprinter to draw the edge.
Most of it I got covered, but one major obstacle remains. When I run my picture through my Sobel and use a binary truncate it returns a 2D int array of 0's and 255's. Just an example of a test array for better understanding.
255 255 255 255 255 255 255 255
255 0 0 0 255 0 0 255
255 255 0 0 0 255 255 255
255 0 0 255 255 0 0 255
255 255 255 0 255 0 0 255
255 0 255 0 0 0 0 255
255 255 255 255 255 255 255 255
I'm then using a nested for loop to go through the array and give me an i coordinate, j coordinate and magnitude for each position in the array, like this. I'm using the StringBuilder, because I need to send a String to the PLC.
public static void stringBuilder(int m)
// start method stringbuilder
StringBuilder sb = new StringBuilder();
for (int i = 0 ; i < m.length ; i++)
// start i for loop
for ( int j = 0 ; j < m[i].length ; j++)
// start j for loop
int magnitude = m[j][i];
/*
sb.append("(");
sb.append(i);
sb.append(",");
sb.append(j);
sb.append(")");
sb.append(" : ");
*/
if (magnitude == 0)
sb.append(magnitude);
sb.append(" ");
else
sb.append(magnitude);
sb.append(" ");
sb.append(" ");
// end j for loop
sb.append("n");
// end i for loop
System.out.println(sb);
// end method stringbuilder
I have also figured out how to print the elements of connected elements like this. This is by row, but have methods by column, diagonaly left and right. Again putting it in a StringBuilder.
for (int i = 0; i < n.length ; i++)
{
for (int j = 0; j < n[0].length ; j++)
int d = j + 1;
int e = j - 1;
if (d < n[0].length)
Now here's the problem. I would very much like to be able to send a string to the PLC containing only the coordinates where it is suppose to draw. In the example array I would be:
0,0 to 0,7 up
1,0 up; 1,1 to 1,3 down; 1,4 up; 1,5 to 1,6 down; 1,7 up
2,0 to 2,1 up ; 2,2 to 2,4 down ; 2,5 to 2,7 up
3,0 up ; 3,1 to 3,2 down ; 3,3 to 3,4 up ; 3,5 to 3,6 down ; 3,7 up
and so on and so forth.
In essence getting a sequense of element in the middle of the array.
The idea behind this is that the differens in j coordinates can be translated to a number of steps in a steppermotor.
I just can't figure out how to do it.
java arrays multidimensional-array
java arrays multidimensional-array
edited Nov 15 '18 at 9:20
Andrea
4,54012144
asked Nov 15 '18 at 7:57
Peter Lindhøj TuxenPeter Lindhøj Tuxen
102
edited Nov 15 '18 at 9:20
Andrea
4,54012144
asked Nov 15 '18 at 7:57
Peter Lindhøj TuxenPeter Lindhøj Tuxen
102
edited Nov 15 '18 at 9:20
Andrea
4,54012144
edited Nov 15 '18 at 9:20
Andrea
4,54012144
edited Nov 15 '18 at 9:20
Andrea
4,54012144
4,54012144
asked Nov 15 '18 at 7:57
Peter Lindhøj TuxenPeter Lindhøj Tuxen
102
asked Nov 15 '18 at 7:57
Peter Lindhøj TuxenPeter Lindhøj Tuxen
102
asked Nov 15 '18 at 7:57
Peter Lindhøj TuxenPeter Lindhøj Tuxen
102
102
add a comment |
add a comment |
2 Answers
2
active
oldest
votes
0
Reading line by line, and checking when the value changes, you can easily manage it.
Here's an example:
public static void main(String args)
int array =
255, 255, 255, 255, 255, 255, 255, 255 ,
255, 0, 0, 0, 255, 0, 0, 255 ,
255, 255, 0, 0, 0, 255, 255, 255 ,
255, 0, 0, 255, 255, 0, 0, 255 ,
255, 255, 255, 0, 255, 0, 0, 255 ,
255, 0, 255, 0, 0, 0, 0, 255 ,
255, 255, 255, 255, 255, 255, 255, 255
;
StringBuilder result = new StringBuilder();
int currentValue;
int startIndex;
for (int i = 0; i < array.length; i++)
if (array[i].length == 0)
continue;
currentValue = array[i][0];
startIndex = 0;
for (int j = 1; j < array[i].length; j++)
if (currentValue != array[i][j])
updateResult(result, currentValue, i, startIndex, j - 1);
currentValue = array[i][j];
startIndex = j;
updateResult(result, currentValue, i, startIndex, array[i].length - 1);
result.append("n");
System.out.println(result.toString());
private static void updateResult(StringBuilder result, int value, int row, int startIndex, int endIndex)
if (startIndex == endIndex)
addCoordinates(result, row, startIndex);
else
addCoordinates(result, row, startIndex);
result.append(" to ");
addCoordinates(result, row, endIndex);
result.append(" ");
switch(value)
case 255:
result.append("up");
break;
case 0:
result.append("down");
break;
default:
System.err.println("Unrecognized value " + value);
result.append("; ");
private static void addCoordinates(StringBuilder result, int row, int column)
result.append(row);
result.append(",");
result.append(column);
For your input array, the result will be:
0,0 to 0,7 up;
1,0 up; 1,1 to 1,3 down; 1,4 up; 1,5 to 1,6 down; 1,7 up;
2,0 to 2,1 up; 2,2 to 2,4 down; 2,5 to 2,7 up;
3,0 up; 3,1 to 3,2 down; 3,3 to 3,4 up; 3,5 to 3,6 down; 3,7 up;
4,0 to 4,2 up; 4,3 down; 4,4 up; 4,5 to 4,6 down; 4,7 up;
5,0 up; 5,1 down; 5,2 up; 5,3 to 5,6 down; 5,7 up;
6,0 to 6,7 up;
answered Nov 15 '18 at 8:57
raven1981raven1981
9401217
Fantastic. Thanks for answers. Will give it a try.
– Peter Lindhøj Tuxen
Nov 15 '18 at 9:18
add a comment |
0
Try out this code:
// String formatting
public static final String FORMAT_TO_UP = "%d,%d to %d,%d up";
public static final String FORMAT_TO_DOWN = "%d,%d to %d,%d down";
public static final String FORMAT_UP = "%d,%d up";
public static final String FORMAT_DOWN = "%d,%d down";
public static void stringBuilder(int m)
// start method stringbuilder
StringBuilder sb = new StringBuilder();
for(int i = 0; i < m.length; i++)
// start i for loop
int upStart = 0;
int downStart = 0;
boolean hasPreviousUp = false;
boolean hasPreviousDown = false;
final int rowSize = m[i].length;
for(int j = 0; j < rowSize; j++)
// start j for loop
int magnitude = m[i][j];
// Reached a down
if(magnitude == 0)
// Handle the change from up to down
if(hasPreviousUp)
// If range is only 1
if(upStart == j - 1)
sb.append(String.format(FORMAT_UP, i, j - 1));
else
sb.append(String.format(FORMAT_TO_UP, i, upStart, i, j - 1));
hasPreviousUp = false;
sb.append("; ");
// Don't reset the start value if there was no change of up/down
if(!hasPreviousDown)
hasPreviousDown = true;
downStart = j;
// Reached an up
else
// Handle the change from down to up
if(hasPreviousDown)
// If range is only 1
if(downStart == j - 1)
sb.append(String.format(FORMAT_DOWN, i, j - 1));
else
sb.append(String.format(FORMAT_TO_DOWN, i, downStart, i, j - 1));
hasPreviousDown = false;
sb.append("; ");
// Don't reset the start value if there was no change of up/down
if(!hasPreviousUp)
hasPreviousUp = true;
upStart = j;
// end j for loop
// Handle the last up/down range
if(hasPreviousUp)
if(upStart == rowSize - 1)
sb.append(String.format(FORMAT_UP, i, rowSize - 1));
else
sb.append(String.format(FORMAT_TO_UP, i, upStart, i, rowSize - 1));
else if(hasPreviousDown)
if(downStart == rowSize - 1)
sb.append(String.format(FORMAT_DOWN, i, rowSize - 1));
else
sb.append(String.format(FORMAT_TO_DOWN, i, downStart, i, rowSize - 1));
sb.append("n");
// end i for loop
System.out.println(sb);
// end method stringbuilder
Result:
0,0 to 0,7 up
1,0 up; 1,1 to 1,3 down; 1,4 up; 1,5 to 1,6 down; 1,7 up
2,0 to 2,1 up; 2,2 to 2,4 down; 2,5 to 2,7 up
3,0 up; 3,1 to 3,2 down; 3,3 to 3,4 up; 3,5 to 3,6 down; 3,7 up
4,0 to 4,2 up; 4,3 down; 4,4 up; 4,5 to 4,6 down; 4,7 up
5,0 up; 5,1 down; 5,2 up; 5,3 to 5,6 down; 5,7 up
6,0 to 6,7 up
answered Nov 15 '18 at 9:11
Justin TayJustin Tay
744
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
0
Reading line by line, and checking when the value changes, you can easily manage it.
Here's an example:
public static void main(String args)
int array =
255, 255, 255, 255, 255, 255, 255, 255 ,
255, 0, 0, 0, 255, 0, 0, 255 ,
255, 255, 0, 0, 0, 255, 255, 255 ,
255, 0, 0, 255, 255, 0, 0, 255 ,
255, 255, 255, 0, 255, 0, 0, 255 ,
255, 0, 255, 0, 0, 0, 0, 255 ,
255, 255, 255, 255, 255, 255, 255, 255
;
StringBuilder result = new StringBuilder();
int currentValue;
int startIndex;
for (int i = 0; i < array.length; i++)
if (array[i].length == 0)
continue;
currentValue = array[i][0];
startIndex = 0;
for (int j = 1; j < array[i].length; j++)
if (currentValue != array[i][j])
updateResult(result, currentValue, i, startIndex, j - 1);
currentValue = array[i][j];
startIndex = j;
updateResult(result, currentValue, i, startIndex, array[i].length - 1);
result.append("n");
System.out.println(result.toString());
private static void updateResult(StringBuilder result, int value, int row, int startIndex, int endIndex)
if (startIndex == endIndex)
addCoordinates(result, row, startIndex);
else
addCoordinates(result, row, startIndex);
result.append(" to ");
addCoordinates(result, row, endIndex);
result.append(" ");
switch(value)
case 255:
result.append("up");
break;
case 0:
result.append("down");
break;
default:
System.err.println("Unrecognized value " + value);
result.append("; ");
private static void addCoordinates(StringBuilder result, int row, int column)
result.append(row);
result.append(",");
result.append(column);
For your input array, the result will be:
0,0 to 0,7 up;
1,0 up; 1,1 to 1,3 down; 1,4 up; 1,5 to 1,6 down; 1,7 up;
2,0 to 2,1 up; 2,2 to 2,4 down; 2,5 to 2,7 up;
3,0 up; 3,1 to 3,2 down; 3,3 to 3,4 up; 3,5 to 3,6 down; 3,7 up;
4,0 to 4,2 up; 4,3 down; 4,4 up; 4,5 to 4,6 down; 4,7 up;
5,0 up; 5,1 down; 5,2 up; 5,3 to 5,6 down; 5,7 up;
6,0 to 6,7 up;
answered Nov 15 '18 at 8:57
raven1981raven1981
9401217
Fantastic. Thanks for answers. Will give it a try.
– Peter Lindhøj Tuxen
Nov 15 '18 at 9:18
add a comment |
0
Reading line by line, and checking when the value changes, you can easily manage it.
Here's an example:
public static void main(String args)
int array =
255, 255, 255, 255, 255, 255, 255, 255 ,
255, 0, 0, 0, 255, 0, 0, 255 ,
255, 255, 0, 0, 0, 255, 255, 255 ,
255, 0, 0, 255, 255, 0, 0, 255 ,
255, 255, 255, 0, 255, 0, 0, 255 ,
255, 0, 255, 0, 0, 0, 0, 255 ,
255, 255, 255, 255, 255, 255, 255, 255
;
StringBuilder result = new StringBuilder();
int currentValue;
int startIndex;
for (int i = 0; i < array.length; i++)
if (array[i].length == 0)
continue;
currentValue = array[i][0];
startIndex = 0;
for (int j = 1; j < array[i].length; j++)
if (currentValue != array[i][j])
updateResult(result, currentValue, i, startIndex, j - 1);
currentValue = array[i][j];
startIndex = j;
updateResult(result, currentValue, i, startIndex, array[i].length - 1);
result.append("n");
System.out.println(result.toString());
private static void updateResult(StringBuilder result, int value, int row, int startIndex, int endIndex)
if (startIndex == endIndex)
addCoordinates(result, row, startIndex);
else
addCoordinates(result, row, startIndex);
result.append(" to ");
addCoordinates(result, row, endIndex);
result.append(" ");
switch(value)
case 255:
result.append("up");
break;
case 0:
result.append("down");
break;
default:
System.err.println("Unrecognized value " + value);
result.append("; ");
private static void addCoordinates(StringBuilder result, int row, int column)
result.append(row);
result.append(",");
result.append(column);
For your input array, the result will be:
0,0 to 0,7 up;
1,0 up; 1,1 to 1,3 down; 1,4 up; 1,5 to 1,6 down; 1,7 up;
2,0 to 2,1 up; 2,2 to 2,4 down; 2,5 to 2,7 up;
3,0 up; 3,1 to 3,2 down; 3,3 to 3,4 up; 3,5 to 3,6 down; 3,7 up;
4,0 to 4,2 up; 4,3 down; 4,4 up; 4,5 to 4,6 down; 4,7 up;
5,0 up; 5,1 down; 5,2 up; 5,3 to 5,6 down; 5,7 up;
6,0 to 6,7 up;
answered Nov 15 '18 at 8:57
raven1981raven1981
9401217
Fantastic. Thanks for answers. Will give it a try.
– Peter Lindhøj Tuxen
Nov 15 '18 at 9:18
add a comment |
0
0
0
Reading line by line, and checking when the value changes, you can easily manage it.
Here's an example:
public static void main(String args)
int array =
255, 255, 255, 255, 255, 255, 255, 255 ,
255, 0, 0, 0, 255, 0, 0, 255 ,
255, 255, 0, 0, 0, 255, 255, 255 ,
255, 0, 0, 255, 255, 0, 0, 255 ,
255, 255, 255, 0, 255, 0, 0, 255 ,
255, 0, 255, 0, 0, 0, 0, 255 ,
255, 255, 255, 255, 255, 255, 255, 255
;
StringBuilder result = new StringBuilder();
int currentValue;
int startIndex;
for (int i = 0; i < array.length; i++)
if (array[i].length == 0)
continue;
currentValue = array[i][0];
startIndex = 0;
for (int j = 1; j < array[i].length; j++)
if (currentValue != array[i][j])
updateResult(result, currentValue, i, startIndex, j - 1);
currentValue = array[i][j];
startIndex = j;
updateResult(result, currentValue, i, startIndex, array[i].length - 1);
result.append("n");
System.out.println(result.toString());
private static void updateResult(StringBuilder result, int value, int row, int startIndex, int endIndex)
if (startIndex == endIndex)
addCoordinates(result, row, startIndex);
else
addCoordinates(result, row, startIndex);
result.append(" to ");
addCoordinates(result, row, endIndex);
result.append(" ");
switch(value)
case 255:
result.append("up");
break;
case 0:
result.append("down");
break;
default:
System.err.println("Unrecognized value " + value);
result.append("; ");
private static void addCoordinates(StringBuilder result, int row, int column)
result.append(row);
result.append(",");
result.append(column);
For your input array, the result will be:
0,0 to 0,7 up;
1,0 up; 1,1 to 1,3 down; 1,4 up; 1,5 to 1,6 down; 1,7 up;
2,0 to 2,1 up; 2,2 to 2,4 down; 2,5 to 2,7 up;
3,0 up; 3,1 to 3,2 down; 3,3 to 3,4 up; 3,5 to 3,6 down; 3,7 up;
4,0 to 4,2 up; 4,3 down; 4,4 up; 4,5 to 4,6 down; 4,7 up;
5,0 up; 5,1 down; 5,2 up; 5,3 to 5,6 down; 5,7 up;
6,0 to 6,7 up;
answered Nov 15 '18 at 8:57
raven1981raven1981
9401217
Reading line by line, and checking when the value changes, you can easily manage it.
Here's an example:
public static void main(String args)
int array =
255, 255, 255, 255, 255, 255, 255, 255 ,
255, 0, 0, 0, 255, 0, 0, 255 ,
255, 255, 0, 0, 0, 255, 255, 255 ,
255, 0, 0, 255, 255, 0, 0, 255 ,
255, 255, 255, 0, 255, 0, 0, 255 ,
255, 0, 255, 0, 0, 0, 0, 255 ,
255, 255, 255, 255, 255, 255, 255, 255
;
StringBuilder result = new StringBuilder();
int currentValue;
int startIndex;
for (int i = 0; i < array.length; i++)
if (array[i].length == 0)
continue;
currentValue = array[i][0];
startIndex = 0;
for (int j = 1; j < array[i].length; j++)
if (currentValue != array[i][j])
updateResult(result, currentValue, i, startIndex, j - 1);
currentValue = array[i][j];
startIndex = j;
updateResult(result, currentValue, i, startIndex, array[i].length - 1);
result.append("n");
System.out.println(result.toString());
private static void updateResult(StringBuilder result, int value, int row, int startIndex, int endIndex)
if (startIndex == endIndex)
addCoordinates(result, row, startIndex);
else
addCoordinates(result, row, startIndex);
result.append(" to ");
addCoordinates(result, row, endIndex);
result.append(" ");
switch(value)
case 255:
result.append("up");
break;
case 0:
result.append("down");
break;
default:
System.err.println("Unrecognized value " + value);
result.append("; ");
private static void addCoordinates(StringBuilder result, int row, int column)
result.append(row);
result.append(",");
result.append(column);
For your input array, the result will be:
0,0 to 0,7 up;
1,0 up; 1,1 to 1,3 down; 1,4 up; 1,5 to 1,6 down; 1,7 up;
2,0 to 2,1 up; 2,2 to 2,4 down; 2,5 to 2,7 up;
3,0 up; 3,1 to 3,2 down; 3,3 to 3,4 up; 3,5 to 3,6 down; 3,7 up;
4,0 to 4,2 up; 4,3 down; 4,4 up; 4,5 to 4,6 down; 4,7 up;
5,0 up; 5,1 down; 5,2 up; 5,3 to 5,6 down; 5,7 up;
6,0 to 6,7 up;
answered Nov 15 '18 at 8:57
raven1981raven1981
9401217
answered Nov 15 '18 at 8:57
raven1981raven1981
9401217
answered Nov 15 '18 at 8:57
raven1981raven1981
9401217
answered Nov 15 '18 at 8:57
raven1981raven1981
9401217
9401217
Fantastic. Thanks for answers. Will give it a try.
– Peter Lindhøj Tuxen
Nov 15 '18 at 9:18
add a comment |
Fantastic. Thanks for answers. Will give it a try.
– Peter Lindhøj Tuxen
Nov 15 '18 at 9:18
Fantastic. Thanks for answers. Will give it a try.
– Peter Lindhøj Tuxen
Nov 15 '18 at 9:18
Fantastic. Thanks for answers. Will give it a try.
– Peter Lindhøj Tuxen
Nov 15 '18 at 9:18
add a comment |
0
Try out this code:
// String formatting
public static final String FORMAT_TO_UP = "%d,%d to %d,%d up";
public static final String FORMAT_TO_DOWN = "%d,%d to %d,%d down";
public static final String FORMAT_UP = "%d,%d up";
public static final String FORMAT_DOWN = "%d,%d down";
public static void stringBuilder(int m)
// start method stringbuilder
StringBuilder sb = new StringBuilder();
for(int i = 0; i < m.length; i++)
// start i for loop
int upStart = 0;
int downStart = 0;
boolean hasPreviousUp = false;
boolean hasPreviousDown = false;
final int rowSize = m[i].length;
for(int j = 0; j < rowSize; j++)
// start j for loop
int magnitude = m[i][j];
// Reached a down
if(magnitude == 0)
// Handle the change from up to down
if(hasPreviousUp)
// If range is only 1
if(upStart == j - 1)
sb.append(String.format(FORMAT_UP, i, j - 1));
else
sb.append(String.format(FORMAT_TO_UP, i, upStart, i, j - 1));
hasPreviousUp = false;
sb.append("; ");
// Don't reset the start value if there was no change of up/down
if(!hasPreviousDown)
hasPreviousDown = true;
downStart = j;
// Reached an up
else
// Handle the change from down to up
if(hasPreviousDown)
// If range is only 1
if(downStart == j - 1)
sb.append(String.format(FORMAT_DOWN, i, j - 1));
else
sb.append(String.format(FORMAT_TO_DOWN, i, downStart, i, j - 1));
hasPreviousDown = false;
sb.append("; ");
// Don't reset the start value if there was no change of up/down
if(!hasPreviousUp)
hasPreviousUp = true;
upStart = j;
// end j for loop
// Handle the last up/down range
if(hasPreviousUp)
if(upStart == rowSize - 1)
sb.append(String.format(FORMAT_UP, i, rowSize - 1));
else
sb.append(String.format(FORMAT_TO_UP, i, upStart, i, rowSize - 1));
else if(hasPreviousDown)
if(downStart == rowSize - 1)
sb.append(String.format(FORMAT_DOWN, i, rowSize - 1));
else
sb.append(String.format(FORMAT_TO_DOWN, i, downStart, i, rowSize - 1));
sb.append("n");
// end i for loop
System.out.println(sb);
// end method stringbuilder
Result:
0,0 to 0,7 up
1,0 up; 1,1 to 1,3 down; 1,4 up; 1,5 to 1,6 down; 1,7 up
2,0 to 2,1 up; 2,2 to 2,4 down; 2,5 to 2,7 up
3,0 up; 3,1 to 3,2 down; 3,3 to 3,4 up; 3,5 to 3,6 down; 3,7 up
4,0 to 4,2 up; 4,3 down; 4,4 up; 4,5 to 4,6 down; 4,7 up
5,0 up; 5,1 down; 5,2 up; 5,3 to 5,6 down; 5,7 up
6,0 to 6,7 up
answered Nov 15 '18 at 9:11
Justin TayJustin Tay
744
add a comment |
0
Try out this code:
// String formatting
public static final String FORMAT_TO_UP = "%d,%d to %d,%d up";
public static final String FORMAT_TO_DOWN = "%d,%d to %d,%d down";
public static final String FORMAT_UP = "%d,%d up";
public static final String FORMAT_DOWN = "%d,%d down";
public static void stringBuilder(int m)
// start method stringbuilder
StringBuilder sb = new StringBuilder();
for(int i = 0; i < m.length; i++)
// start i for loop
int upStart = 0;
int downStart = 0;
boolean hasPreviousUp = false;
boolean hasPreviousDown = false;
final int rowSize = m[i].length;
for(int j = 0; j < rowSize; j++)
// start j for loop
int magnitude = m[i][j];
// Reached a down
if(magnitude == 0)
// Handle the change from up to down
if(hasPreviousUp)
// If range is only 1
if(upStart == j - 1)
sb.append(String.format(FORMAT_UP, i, j - 1));
else
sb.append(String.format(FORMAT_TO_UP, i, upStart, i, j - 1));
hasPreviousUp = false;
sb.append("; ");
// Don't reset the start value if there was no change of up/down
if(!hasPreviousDown)
hasPreviousDown = true;
downStart = j;
// Reached an up
else
// Handle the change from down to up
if(hasPreviousDown)
// If range is only 1
if(downStart == j - 1)
sb.append(String.format(FORMAT_DOWN, i, j - 1));
else
sb.append(String.format(FORMAT_TO_DOWN, i, downStart, i, j - 1));
hasPreviousDown = false;
sb.append("; ");
// Don't reset the start value if there was no change of up/down
if(!hasPreviousUp)
hasPreviousUp = true;
upStart = j;
// end j for loop
// Handle the last up/down range
if(hasPreviousUp)
if(upStart == rowSize - 1)
sb.append(String.format(FORMAT_UP, i, rowSize - 1));
else
sb.append(String.format(FORMAT_TO_UP, i, upStart, i, rowSize - 1));
else if(hasPreviousDown)
if(downStart == rowSize - 1)
sb.append(String.format(FORMAT_DOWN, i, rowSize - 1));
else
sb.append(String.format(FORMAT_TO_DOWN, i, downStart, i, rowSize - 1));
sb.append("n");
// end i for loop
System.out.println(sb);
// end method stringbuilder
Result:
0,0 to 0,7 up
1,0 up; 1,1 to 1,3 down; 1,4 up; 1,5 to 1,6 down; 1,7 up
2,0 to 2,1 up; 2,2 to 2,4 down; 2,5 to 2,7 up
3,0 up; 3,1 to 3,2 down; 3,3 to 3,4 up; 3,5 to 3,6 down; 3,7 up
4,0 to 4,2 up; 4,3 down; 4,4 up; 4,5 to 4,6 down; 4,7 up
5,0 up; 5,1 down; 5,2 up; 5,3 to 5,6 down; 5,7 up
6,0 to 6,7 up
answered Nov 15 '18 at 9:11
Justin TayJustin Tay
744
add a comment |
0
0
0
Try out this code:
// String formatting
public static final String FORMAT_TO_UP = "%d,%d to %d,%d up";
public static final String FORMAT_TO_DOWN = "%d,%d to %d,%d down";
public static final String FORMAT_UP = "%d,%d up";
public static final String FORMAT_DOWN = "%d,%d down";
public static void stringBuilder(int m)
// start method stringbuilder
StringBuilder sb = new StringBuilder();
for(int i = 0; i < m.length; i++)
// start i for loop
int upStart = 0;
int downStart = 0;
boolean hasPreviousUp = false;
boolean hasPreviousDown = false;
final int rowSize = m[i].length;
for(int j = 0; j < rowSize; j++)
// start j for loop
int magnitude = m[i][j];
// Reached a down
if(magnitude == 0)
// Handle the change from up to down
if(hasPreviousUp)
// If range is only 1
if(upStart == j - 1)
sb.append(String.format(FORMAT_UP, i, j - 1));
else
sb.append(String.format(FORMAT_TO_UP, i, upStart, i, j - 1));
hasPreviousUp = false;
sb.append("; ");
// Don't reset the start value if there was no change of up/down
if(!hasPreviousDown)
hasPreviousDown = true;
downStart = j;
// Reached an up
else
// Handle the change from down to up
if(hasPreviousDown)
// If range is only 1
if(downStart == j - 1)
sb.append(String.format(FORMAT_DOWN, i, j - 1));
else
sb.append(String.format(FORMAT_TO_DOWN, i, downStart, i, j - 1));
hasPreviousDown = false;
sb.append("; ");
// Don't reset the start value if there was no change of up/down
if(!hasPreviousUp)
hasPreviousUp = true;
upStart = j;
// end j for loop
// Handle the last up/down range
if(hasPreviousUp)
if(upStart == rowSize - 1)
sb.append(String.format(FORMAT_UP, i, rowSize - 1));
else
sb.append(String.format(FORMAT_TO_UP, i, upStart, i, rowSize - 1));
else if(hasPreviousDown)
if(downStart == rowSize - 1)
sb.append(String.format(FORMAT_DOWN, i, rowSize - 1));
else
sb.append(String.format(FORMAT_TO_DOWN, i, downStart, i, rowSize - 1));
sb.append("n");
// end i for loop
System.out.println(sb);
// end method stringbuilder
Result:
0,0 to 0,7 up
1,0 up; 1,1 to 1,3 down; 1,4 up; 1,5 to 1,6 down; 1,7 up
2,0 to 2,1 up; 2,2 to 2,4 down; 2,5 to 2,7 up
3,0 up; 3,1 to 3,2 down; 3,3 to 3,4 up; 3,5 to 3,6 down; 3,7 up
4,0 to 4,2 up; 4,3 down; 4,4 up; 4,5 to 4,6 down; 4,7 up
5,0 up; 5,1 down; 5,2 up; 5,3 to 5,6 down; 5,7 up
6,0 to 6,7 up
answered Nov 15 '18 at 9:11
Justin TayJustin Tay
744
Try out this code:
// String formatting
public static final String FORMAT_TO_UP = "%d,%d to %d,%d up";
public static final String FORMAT_TO_DOWN = "%d,%d to %d,%d down";
public static final String FORMAT_UP = "%d,%d up";
public static final String FORMAT_DOWN = "%d,%d down";
public static void stringBuilder(int m)
// start method stringbuilder
StringBuilder sb = new StringBuilder();
for(int i = 0; i < m.length; i++)
// start i for loop
int upStart = 0;
int downStart = 0;
boolean hasPreviousUp = false;
boolean hasPreviousDown = false;
final int rowSize = m[i].length;
for(int j = 0; j < rowSize; j++)
// start j for loop
int magnitude = m[i][j];
// Reached a down
if(magnitude == 0)
// Handle the change from up to down
if(hasPreviousUp)
// If range is only 1
if(upStart == j - 1)
sb.append(String.format(FORMAT_UP, i, j - 1));
else
sb.append(String.format(FORMAT_TO_UP, i, upStart, i, j - 1));
hasPreviousUp = false;
sb.append("; ");
// Don't reset the start value if there was no change of up/down
if(!hasPreviousDown)
hasPreviousDown = true;
downStart = j;
// Reached an up
else
// Handle the change from down to up
if(hasPreviousDown)
// If range is only 1
if(downStart == j - 1)
sb.append(String.format(FORMAT_DOWN, i, j - 1));
else
sb.append(String.format(FORMAT_TO_DOWN, i, downStart, i, j - 1));
hasPreviousDown = false;
sb.append("; ");
// Don't reset the start value if there was no change of up/down
if(!hasPreviousUp)
hasPreviousUp = true;
upStart = j;
// end j for loop
// Handle the last up/down range
if(hasPreviousUp)
if(upStart == rowSize - 1)
sb.append(String.format(FORMAT_UP, i, rowSize - 1));
else
sb.append(String.format(FORMAT_TO_UP, i, upStart, i, rowSize - 1));
else if(hasPreviousDown)
if(downStart == rowSize - 1)
sb.append(String.format(FORMAT_DOWN, i, rowSize - 1));
else
sb.append(String.format(FORMAT_TO_DOWN, i, downStart, i, rowSize - 1));
sb.append("n");
// end i for loop
System.out.println(sb);
// end method stringbuilder
Result:
0,0 to 0,7 up
1,0 up; 1,1 to 1,3 down; 1,4 up; 1,5 to 1,6 down; 1,7 up
2,0 to 2,1 up; 2,2 to 2,4 down; 2,5 to 2,7 up
3,0 up; 3,1 to 3,2 down; 3,3 to 3,4 up; 3,5 to 3,6 down; 3,7 up
4,0 to 4,2 up; 4,3 down; 4,4 up; 4,5 to 4,6 down; 4,7 up
5,0 up; 5,1 down; 5,2 up; 5,3 to 5,6 down; 5,7 up
6,0 to 6,7 up
answered Nov 15 '18 at 9:11
Justin TayJustin Tay
744
answered Nov 15 '18 at 9:11
Justin TayJustin Tay
744
answered Nov 15 '18 at 9:11
Justin TayJustin Tay
744
answered Nov 15 '18 at 9:11
Justin TayJustin Tay
744
744
add a comment |
add a comment |
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