2D Array Computation - Performing Certain Matrix Calculations
Apr 22, 2015
I've created several methods in another class to perform certain matrix calculations. Do I need to have mutator method in this calculation class to define the column length of the matrix object? I understand why the following code is not working, but I was hoping to get a quick and easy workaround. I'm not sure how to initialize the size of the column for newMatrix within the method.
public int [][] sum(int matrixOne[][], int matrixTwo[][]) {
int sumMatrix [][] = new int[matrixOne.length]["WHAT TO PUT HERE"];
for (int i = 0; i < matrixOne.length; i++) {
for (int j = 0; j < matrixOne[i].length; j++) {
sumMatrix[i][j] = matrixOne[i][j] + matrixTwo[i][j];
System.out.println("matrixSum" + sumMatrix[i][j]);
}
}
return sumMatrix;
}
Then I will use this method to print the new matrix:
public void printMatrix(int newMatrix [][]) {
for (int i = 0; i < newMatrix.length; i++) {
for (int j = 0; j < newMatrix[i].length; j++) {
System.out.print(newMatrix[i][j] + " ");
}
System.out.println("");
}
}
Is all of this overkill and should I just define all the methods within the same class to avoid these issues?
It seems that all of my arrays in the class Calculations are out of bounds, and I do not seem to know why.
Java Code:
/** public class DataAnalyzer { public static void main (String[] args) { //This creates an instance of ReadFiles ReadFiles aReadFiles = new ReadFiles(); Calculations aCalculations = new Calculations();
Write the Java code of the method Transpose2D that takes one 2-dimentional array (matrix) A and returns one 2-dimentional array B that is transpose of matrix A. (assume that all the rows are of the same length)
public int[][] transpose (int[][] array) { if (array == null || array.length == 0)//empty or unset array, nothing do to here return array; int width = array.length; int height = array[0].length;
public class matrix_mul { static int a[][],b[][],k; public static void main(String o[]) { k=0; a=new int[3][3]; b=new int[3][3];
[Code] ....
Well, this is my code for inserting values in 2D array for matrix & then printing it on Command line but it's show ArrayIndexOutOfBoundExcepton 3 or sometimes 1 (on cmd) ....
I am working with an Adjacency Matrix to try to find the MST of a graph. Along the way I have hit a snag that I am not sure how to get around. When running the program I will parse through each row of the matrix and find the smallest weight. However when trying to reset the row at the end of the lowest sort I cannot move to the next row.
The graph looks like this:
My Matrix was created from the graph and I have determined by starting at Vertex W my path should looks like this: W->R->D->H->G->S->C->B->A
import java.io.*; public class workhours{ public static void main (String args[]){ try{ BufferedReader breader=new BufferedReader(new InputStreamReader(System.in)); String days[]={"Monday","Tuesday","Wednesday","Thursday","Friday","Saturday"};
The problem is, the values are completely different than they are saved in MATLAB, and probably I need to shift the values after transforming them into byte arrays.My Java code which reads values of floating numbers from a MATLAB bin file as follows:
import java.io.*; import java.io.File; import javax.imageio.ImageIO; import java.nio.ByteBuffer; // may be useful? public class floatingNumberMatrixReader {
I have some problems about performing regular expression. In the following code, the output as a result is being "valid last name". But in my opinion, it should be "invalid last name". Because "Doe" has not any space, apostroph or any hypen. Look at the regular expression statement: "[a-zA-Z]+([ '-][a-zA-Z]+)*"
package deneme; public class Deneme { public static void main(String[] args) { String lastName = "Mc-Something"; // Mc-Something if(!lastName.matches("[a-zA-Z]+([ '-][a-zA-Z]+)*")) System.out.println("Invalid last name"); else System.out.println("Valid last name"); } }
I know that the asterisk qualifier means character(s) in any number.(Is this wrong?) So for "Mc-Something", 'M' corresponds to [a-zA-Z], 'c' corresponds to +, - corresponds to [ '-], 'S' corresponds to [a-zA-Z], "o" corresponds to +, and finally "mething" corresponds to *, doesn't they? But for "Doe", there is no any space, apostroph or hypen.
Given a LISP expression, perform operations on the expression. There will be no list elements that also contain a list such as '(A (B (C D))), which has one atom and one list but the list contains a sublist
INPUT: There will be 5 lines of input. Each line will contain a valid LISP expression. There will be a space between each atom and each list. There are no spaces immediately after or immediately before parentheses in a list. The entire expression must be inputted as a single string.
OUPUT: Perform the given operation on the like numbered expression. The 5 operations are:
1. Print the expression with the list in reverse order. The list will contain only atoms.
2. Print the expression with the list written with consecutive duplicates encoded as sublists in (count element) order. The list will contain only atoms.
3 Print the expression with the list written with consecutive duplicates encoded as sublists in (count element) order except that singletons are listed as atoms. The list will contain only atoms.
4. Print the expression with the list written with every Nth element deleted and where N is the last element of the list.
5. Print the expression written as 2 expressions where the number of lists in first expression is the last element of the expression.
SAMPLE INPUT SAMPLE OUTPUT 1. '(A B C D) 1. ′(D C B A) 2. '(A A A A B C C A A D E E E E) 2. ′((4 A) (1 B) (2 C) (2 A) (1 D) (4 E)) 3. '(A A A A B C C A A D E E E E) 3. ′((4 A) B (2 C) (2 A) D (4 E)) 4. '((4 A) (1 B) (2 C) (2 A) (1 D) (4 E) 2) 4. ′((4 A) (2 C) (1 D) 2) 5. '((4 A) (1 B) (2 C) (2 A) (1 D) (4 E) 3) 5. ′((4 A) (1 B) (2 C)) ′((2 A) (1 D) (4 E) 3)
This may be a multipart question. Basically I have to write a program that accepts a string, converts it to a double splits it and then performs a calculation.
public static void main(String[] args) { String input = ""; // initalize the string boolean isOn = true; // used for the while loop...when false, the program will exit. String exitCommand = "Exit"; // exit command String[] token = input.split(("(?<=[-+*/])|(?=[-+*/])"));
[Code] ....
This is the error I get:
Enter a math problemException in thread "main" java.lang.NumberFormatException: empty String at sun.misc.FloatingDecimal.readJavaFormatString(Floa tingDecimal.java:1842) at sun.misc.FloatingDecimal.parseDouble(FloatingDecim al.java:110) at java.lang.Double.parseDouble(Double.java:538) at Calculator.main(Calculator.java:22)
[Code] .....
How do I go about actually fixing it. Without that line commented out I get this:
Enter a math problem 2+2 <-What I entered [Ljava.lang.String;@135fbaa4
Also, how would I go about using the submethods to check for valid operands and operators (also part of the problem) I have the actual lists made obviously, but am unsure how to get those to work with the problem.
I want a simple jsp page that performs basic operations on numbers such as addition, subtraction, multiplication, division and modulus . How to run that file?
importjava.util.Scanner; public class ManageAccounts {
[Code].....
and i need to create a .dat file and have it perform the tasks it states, what to do, I've just been looking for existing codes and trying to modify them because i have a very limited knowledge of programming.
I am new Java Programming and I am struggling to pass my Java class. How to perform Java but I am trying. For this particular assignment I supposed to:
* Change all variables' data types to double. * Change the two prompts to request double values * Change change the two calls to the nextInt() method to nextDouble().
This is the original assignment:
import java.util.Scanner; public class ArithmeticDemo { public static void main(String[] args) { Scanner input= new Scanner(System.in); int firstNumber; int secondNumber; int sum; int difference; int average;
How do I create an instance of a class in a method?
I am a bit rusty whenever I think of instances. I always think of main method and objects when I see instance which gets me confused on what to do when I am not in a main method. The example:
I have a abstract class, School, and inside School I have some methods that must preform some action on an instance. For example, there is a move() method that must move the instance of School. Another method named, personOld(), which returns whether or not an instance of School surpassed some determined age.
How do I keep an item (TreeItem) from being selected when performing a drag -n- drop? I don't want it to be selected because it will end up making the target disappear (selection of TreeItem changes target panel).
Related question: Is there a way to "veto" a tree selection change as well?
I have in my application a button that when it is pressed, runs a long running task (usually takes a couple of seconds....).
My problem is that while the task runs, I want to stop the button from receiving clicks. Unfortunately this is something I have not achieved.
I have tried creating a new thread and calling the long running method, and using the Display.geCurrent().asyncExec...
Examples of what I have tried so far:
myButton.addSelectionListener(new SelectionAdapter() { @Override public void widgetSelected(SelectionEvent e) { if (myList.size() > 0) { myButton.setEnabled(false); myButton.setGrayed(true);
[Code] .....
In both cases, while the button is disabled and the cursor busy, if the user clicks the button, the long running method is ran several times - and this is what I want to avoid.
I am almost done with the assignment, but I am having an issue with this step: "Create a field to hold the gallery commission. This field cannot be set from outside the class. it is computed as 20% of the price, and should be set whenever the price is set. Put the code to calculate and set the commission in the setPrice() method"
import java.util.Scanner; public class PaintingHarness { public static void main(String[] args) { // put code here // Created object so we can take input from the Scanner Scanner input = new Scanner(System.in); Painting myPainting = new Painting();
I've created a method to calculate the ratio of one vowel to another, but I was hoping to get some feedback on another way I could approach the problem. The first bit of code is to find the vowels and assign them to an array ( for me, it seemed the easier thing to do in order to easily access the data). In the other bit of code, I have a method with two arguments (the vowels) to calculate the ratio.
public void findVowels(StringBuilder message, String delimiter) { subString = message.toString().toLowerCase().split(delimiter); vowelCounter = new int[5][subString.length]; // Remove all whitespace for (int index = 0; index < subString.length; index++) { subString[index] = subString[index].replaceAll("s", "");
A complex number is defined as z=a+i*b, where a is the real part, and b is the imaginary part. In other words, in order to define a complex number, we need the two floating numbers a and b. Write methods that perform for each of the following operations with complex numbers z1 = a1 + i*b1, and z2 = a2 + i*b2:
Create a test program that asks for the real and imaginary parts of two complex numbers from the user, and displays the results of the four operations, writing the formula as shown above, and replacing the a1, a2, b1 and b2 with the numbers entered by the user.The professor used the incorrect complex number equations and has notified the students of his error. I have run into a few problems thus far.
1. I'm not sure how to use floating numbers with the Math.pow(double, double) function, since its requires doubles!? So instead of using floating numbers, I've knowingly switched them all to double in order to see if the code itself is working properly for the purposes of this forum. Is there a way that I can modify this function so that it will work for floating numbers?
2. Regarding the division method, an error stating that c and d have not been initialized and I'm not sure how to change it because the other calculation methods work fine. Why do I need to initialize c and d in the division method and not the others?
3. Am I on the right path? I have surfed the web to see how others completed the program and they all appear very different than mine...
package program5; import java.util.Scanner; public class Program5 { static double a, b, c, d; static double i = Math.pow(-1,1/2);
I have made a simple form, it consists of 3 text box's textbox1, textbox2 and textbox3 as well as 1 button button1. What I want to be able to do is put numbers into textbox 1 and 2 and then show the multiplication of these numbers in textbox 3 when the button is pressed and I was wondering what is the standard way of reading these numbers from the text box and allowing us to do the conversion obviously in the textbox its a string and we need to convert to an int or double or whatever to be able to perform calculations on them then convert it back into a string to display in text box 3?
I also have this code that takes the file, goes through each line using a loop and counts the total of all the integers on each line, it also then loops and takes each integer on each line and divides it by the total calculated in the previous loop but I don't know what code to manipulate the strings to do these calculations. After these calculations I want to write the updated values to the text file I originally took the data in from. So as an example the total I already for this file to be '232' so the first line would be D 0.06 because 14/232 = 0.06034482758 and rounded to 2 decimal points is 0.06.
I am having problems figuring out how to make calculations using a two dimensional array. The problem is finding the distance of a projectile given the launch velocity and angle. The equation is x = v^2*sin(2theta)/g. I understand how to implement this equation using the toRadians() and Sin() methods. What I don't understand is how to calculate the distance values with a multi dimensional array.
My array has the velocities on the left and angles on the right. I tried using nested loops but I don't know how to access the two pieces of data at a time which I need.
It's an RMI program that has to be able to return the mean, mode and median of a set of numbers.It's composed of 4 classes; a client, an implementation class (with the math), an Interface, and a server class.
