Array questions

Hi, everyone.
I'm writing a lab program which counts the number of occurances of English letters in a line of English text.
The program has the following requirements
Assume that we input only lowercase English text
The program should be able to count the number of occurances of English letters in a text and print out both the number of occurances and the letters. Don't print out letters that don't exist in the text.
I write my code as following:
import java.util.*;
public class Translator
public static void main(String[]args)
     Scanner sc = new Scanner(System.in);
     System.out.println("Please enter text:");
     String text = sc.nextLine();
     char[] input = text.toCharArray();
    public static void countLetters(char [] input)
        System.out.println("Letter           Number of occurances");
        int[] alphabet = new int[26];
        for (int i=0; i<input.length; i++)
            if (input=='a')
alphabet[0] += 1;
else if(input[i]=='b')
alphabet[1] += 1;
else if (input[i]=='c')
alphabet[2] += 1;
else if (input[i]=='d')
alphabet[3] += 1;
else if (input[i]=='e')
alphabet[4] += 1;
else if (input[i]=='f')
alphabet[5] += 1;
else if (input[i]=='g')
alphabet[6] += 1;
else if (input[i]=='h')
alphabet[7] += 1;
else if (input[i]=='i')
alphabet[8] += 1;
else if (input[i]=='j')
alphabet[9] += 1;
else if (input[i]=='k')
alphabet[10] += 1;
else if (input[i]=='l')
alphabet[11] += 1;
else if (input[i]=='m')
alphabet[12] += 1;
else if (input[i]=='n')
alphabet[13] += 1;
else if (input[i]=='o')
alphabet[14] += 1;
else if (input[i]=='p')
alphabet[15] += 1;
else if (input[i]=='q')
alphabet[16] += 1;
else if (input[i]=='r')
alphabet[17] += 1;
else if (input[i]=='s')
alphabet[18] += 1;
else if (input[i]=='t')
alphabet[19] += 1;
else if (input[i]=='u')
alphabet[20] += 1;
else if (input[i]=='v')
alphabet[21] += 1;
else if (input[i]=='w')
alphabet[22] += 1;
else if (input[i]=='x')
alphabet[23] += 1;
else if (input[i]=='y')
alphabet[24] += 1;
else alphabet[25] +=1;
System.out.println("a");
for(int i=0; i<input.length; i++)
if (alphabet[i] > 0)
System.out.println(input[i] +" "+alphabet[i]);
Though having gotten no syntext error complain from the compiler, no matter what I input, the program returns nothing. At first I assumed that it's the first for loop's problem, so that I typed in some System.out.println() methods at the end of some elseif statements. But I still got nothing after this trial. So that I guess it's the char[] input = text.toCharArray();'s problem.
Have the input[i] elements really stored any character (I tried to convert the input string into char array) after I typed char[] input = text.toCharArray();'s problem. ?
My another question is: since the input[i] stores character, when I am trying to print out the letters that exist in the text through the last System.out.println() method in my code, I can use input[i] to represent the letter which I want to print. Is it right?

I figure out now that the problem is caused by the last for loop. I modify it as following:
for(i=0; i<26; i++)
            if (alphabet[i] > 0)
            System.out.println('a'+i +"          "+alphabet);
}After the modification, now I can get the right answer. The only problem I have now is trying to convert the interger number produced by 'a'+i back into character. I tried to replace 'a'+i with toChar('a'+i), but it doesn't work. Can you give me some explanation? Thank you very much!

Similar Messages

Trying to send multiple types in a byte array -- questions?

Hi,
I have a question which I would really appreciate any help on.
I am trying to send a byte array, that contains multiple types using a UDP app. and then receive it on the other end.
So far I have been able to do this using the following code. Please note that I create a new String, Float or Double object to be able to correctly send and receive. Here is the code:
//this is on the client side...
String mymessage ="Here is your stuff from your client" ;
int nbr = 22; Double nbr2 = new Double(1232.11223);
Float nbr3 = new Float(8098098.809808);
ByteArrayOutputStream baos = new ByteArrayOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(baos);
oos.writeObject(mymessage);
oos.writeInt(nbr);
oos.writeObject(nbr2);
oos.writeObject(nbr3);
oos.close();
byte[] buffer = baos.toByteArray();
socket.send(packet);
//this is on the server side...
byte [] buffer = new byte [5000];
String mymessage = null; int nbr = 0; Double nbr2 = null;
Float nbr3 = null;
mymessage = (String)ois.readObject();
nbr = ois.readInt();
nbr2 = (Double) ois.readObject();
nbr3 = (Float) ois.readObject();
My main question here is that I have to create a new Float and Double object to be able to send and receive this byte array correctly. However, I would like to be able to have to only create 1object, stuff it with the String, int, Float and Double, send it and then correctly receive it on the other end.
So I tried creating another class, and then creating an obj of this class and stuffing it with the 4 types:
public class O_struct{
//the indiv. objects to be sent...
public String mymessage; public int nbr; public Double nbr2;
public Float nbr3;
//construct...
public O_struct(String mymessage_c, int nbr_c, double nbr2_c, float nbr3_c){
my_message = my_message_c;
nbr = nbr_c;
nbr2 = new Double(nbr2_c);
nbr3 = new Float(nbr3_c);
Then in main, using this new class:
in main():
O_struct some_obj_client = new O_struct("Here is your stuff from your client", 22, 1232.1234, 890980980.798);
oos.writeObject(some_obj_client);
oos.close();
send code....according to UDP
However on the receiving side, I am not sure how to be able to correctly retrieve the 4 types. Before I was explicitely creating those objects for sending, then I was casting them again on the receiving side to retrieve then and it does work.
But if I create a O_struct object and cast it as I did before with the indiv objects on the receiving end, I can't get the correct retrievals.
My code, on the server side:
O_struct some_obj_server = new O_struct(null, null, null. null);
some_obj_server = (O_struct)ois.readObject();
My main goal is to be able to send 4 types in a byte array, but the way I have written this code, I have to create a Float and Double obj to be able to send and receive correctly. I would rather not have to directly create these objects, but instead be able to stuff all 4 types into a byte array and then send it and correctly be able to retrieve all the info on the receiver's side.
I might be making this more complicated than needed, but this was the only way I could figure out how to do this and any help will be greatly appreciated.
If there an easier way to do I certainly will appreciate that advise as well.
Thanks.

public class O_struct implements Serializable {
// writing
ObjectOutputStream oos = ...;
O_struct struct = ...;
oos.writeObject(struct);
// reading
ObjectInputStream ois = ...;
O_struct struct = (O_struct)ois.readObject();
I will be sending 1000s of these byte arrays, and I'm sure having to create a new Double or Float on both ends will hinder this.
I am worried that having to create new objs every time it is sending a byte array will affect my application.
That's the wrong way to approach this. You're talking about adding complexity to your code and fuglifying it because you think it might improve performance. But you don't know if it will, or by how much, or even if it needs to be improved.
Personally, I'd guess that the I/O will have a much bigger affect on performance than object creation (which, contrary to popular belief, is generally quite fast now: http://www-128.ibm.com/developerworks/java/library/j-jtp01274.html)
If you think object creation is going to be a problem, then before you go and cock up your real code to work around it, create some tests that measure how fast it is one way vs. the other. Then only use the cock-up if the normal, easier to write and maintain way is too slow AND the cock-up is significantly faster.

Database array questions

Disclaimer: I am new to DB's.
I'm looking at creating a MySQL database to hold tests done on DUTs (each with a specific serial). In theory, each DUT undergoes 3 tests. Each test produces a 401x9 2D array of DBLs. I am not concerned with the write speed to the DB, but I do want to optimize the read of the DB (potentially may need to retrieve 1000+ of these 2D arrays as fast as possible). I have the DB Toolkit; using LV 8.5. Questions:
1. I have seen two different ways to save a 2D array in a DB mentioned: first, writing one row at a time with the DB Insert vi, resulting in a 2D array in a table (which is slow writing) or second, changing the 2D array to a variant and using the DB Insert vi, resulting in a single cell in a table. I know I can use other methods (parameterized vi, sql commands, user defined functions on the DB server, please do comment if you have found drastic performance increase with these methods), but of the two ways of storing a 2D array, can I read a 2D array from a table faster than reading a 2D array from a single cell? Whenever I need this data, I will read it all (i.e. I will never have to search for certain data within these individual 2D arrays)
2. I may have installed the 8.2.1 DB toolkit, because the Database Variant to Data vi/function does not drop onto the Block Diagram when I drag it from the palette, and the Help has ???. I assume this is because it just points to the normal Variant to Data, which in 8.5 is in a subpalette as compared to 8.2.1. Any quick way to fix this?
3. Any other general suggestions for a DB newbie? I've been trying to derive best practices from KB aritcles, this forum, and the web, but there is so much information and so many varying opinions I find it hard to narrow down best practices.
Michael

Hi Miguel,
It looks like you are embarking on a very interesting project. Although you probably have seen many of the following documents, I've linked a few to get you started.
Discussion forum using LabVIEW to read from tables
Developer Zone article about developing a test system
Knowledgebase article about imitations of speed with database toolset
As far as your first question, I would suggest trying out both methods with simple code and testing with a small amount of values to determine which one will be the fastest.
Good luck with your project!
Amanda Howard
Americas Services and Support Recruiting Manager
National Instruments

Photo Array Question

I have a bit of a silly question about the photo array Apple uses in many of their publications, including the idea behind "CoverFlow". Check this link to see what I mean: http://arstechnica.com/reviews/os/mac-os-x-10-5.ars/2. (Bottom photo)
Is there a way to achieve this? What software accomplishes this? I am a webmaster using iWeb.
I have something similar on the page I have created, but the difference is my photos are straight as they descend, whereas Apple's are straight, yet not square, they seem to be turned, like in this top image of Ubuntu: http://www.taimila.com/?q=node/3. The photos are not rotated, but turned.
Any software ideas?
Any ideas at all?

Resizing is a different issue altogether from format.
It's safe to scale the image in ID regardless of the format. If you look in the info panel with the image selected you'll see two resolution numbers listed, actual and effective. Actual is just the resolution at the dimensions the image was saved and is essentially irrelevant. Effective resolution is what you have at the dimensions you are currently using, and that's the number that counts. If that number is in the range that is acceptable for the type of output you are using, there is no need to resize the image in Photoshop at all.
If you MUST resize the image, then yes, convert to something besides jpeg if that's what it is to start. And keep in mind that up-sampling won't improve image quality in general, and downsampling more than 20% or so can cause you to lose fine details (but so will scaling down).
Peter

FLV Array question - final flv file looping

So the first part of my question was kindly and quickly
answered by Rothrock. But I've got a new question that has arisen.
When I set these up as an array it's ignoring the settings in the
parameter field for autorewind which is set to false and it's
looping the last movie file in the array. Is there anyway to avoid
this by adding a snippet of new code to this code below:
import mx.controls.MediaDisplay;
flvURL = new Array();
flvURL[1] = "preroll_live.flv";
flvURL[2] = "atlas.flv";
flvURL[3] = "jones_outro.flv";
counter = 1;
my_FLVplybk.contentPath = flvURL[1];
var listenerObject:Object = new Object();
listenerObject.complete = function(eventObject:Object):Void {
counter++;
if (counter == flvURL) {
counter = 1;
my_FLVplybk.contentPath = flvURL[counter];
my_FLVplybk.addEventListener("complete", listenerObject);
Preferably I'd like to either:
Have the movie reset to an array file of my choice but not
auto play or just Stop the movie on the final frame.
Any help here will be greatly appreciated.
Many thanks!
-Kjup

Anyone have any ideas on this...let me know if you need more
details.
Thanks,
Kjup

Sort an array question

Hello I have a sort question.
I have a array like this
"105016""Testnaam 16""16""16"" 16 16 1""105017""Testnaam 17""17""17"" 17 17 2""105018""Testnaam 18""18""18"" 18 18 3""105019""Testnaam 19""19""19"" 19 19 4""105020""Testnaam 20""20""20"" 20 20 5"This 105016 is the record number with data after it "Testnaam 16""16""16"" 16 16 1"
Than there is new data "Testnaam 17""17""17"" 17 17 2" with record number 105017
This is the way it should be because it is good sorted like you can see
first. 105016
than next record 105017
than next record 105018
than next record 105019
than next record 105020
It is in the right order but it can happen that record 105017 is before 105016 because something happend.
All data is stored in an array like I said.
Is it possible to go with a loop through the array and sort it the way I want it but with the data of the record after it???

Hello I made this sorter.
But does someone have some tips if there is a better way to do it.
public class sorttest
public static void main(String[] args)
    String[] data = {"2","boe","schrik","6","hoioi","b","5","test","hoi","9","doei","iets"};
    int[] inar = new int[data.length/3];
    String[] collected= new String [data.length];
    for (int i=0;i<data.length;i+=3)
      inar[i/3]=Integer.valueOf(data).intValue();
int max = inar[0];
for (int i=0;i<inar.length;i++)
if(inar[i]>max)
max=inar[i];
int col=0;
for (int i=0;i<(max+1);i++)
for (int j=0;j<inar.length;j++)
if(inar[j]==i)
String test =""+inar[j];
int cnt= Integer.valueOf(test).intValue();
String iets = ""+cnt;
for(int k=0;k<data.length;k++)
if (iets.equals(data[k]))
     collected[col] = data[k]+" "+data[k+1]+" "+data[k+2];
     System.out.println("DATA OUT "+collected[col]+" COL "+col);
     col++;

Arrays Question

Hello all, i have a couple of questions about multi-dimensional arrays.
The length of this 2-dimensional array is 3.
int table[] [] = {
{1, 2, 3},
{4, 5},
{6, 7, 8, 9},
But what is the length of both own dimensions? How many rows({}) belong to each dimension?
So, what are ? and ? int table [] [] = new int [?] [?] or is it not possible to have a value for ? and ? if you initialized the 2d array?
"Length= number of arrays stored in the multidimension." is this definition good?
int t, i;
int table [] [] = new int [3] [4];
for(t=0; t<3; ++t){
for(i=0; i<4; ++i){
table[t] = (t*4) + i + 1;
system.out.print(table [t] [i] + � �; } system.out.println();
The size of this not initialized 2-dimensional array is 3,4(like in a real table, 3 vertical indexes, and 4 horizontal indexes). But, does this 2-dimensional array have a length(number of arrays), if yes, what is the length of this?

import java.util.Arrays;
import java.util.Random;
public class ArrayOfArrays {
    private int[][] data;
    public ArrayOfArrays(int rows, int cols) {
        data = new int[rows][cols];
    //numbers in the range lo <= x < hi
    public void fillWithRandomNumbers(int lo, int hi) {
        Random r = new Random();
        for(int[] row: data) {
            for(int i =0; i<row.length; ++i) {
                row[i] = lo + r.nextInt(hi-lo);
    public void display() {
        for(int[] row: data) {
            System.out.println(Arrays.toString(row));
    public static void main(String[] args) {
        ArrayOfArrays app = new ArrayOfArrays(5,10);
        app.fillWithRandomNumbers(10,20);
        app.display();
}

Rc.conf deamons array - question

i have a question about the deamon array in rc.conf, this is mine:
DAEMONS=(preload syslog-ng dbus acpid netfs alsa crond hal acpi-support fam stbd wicd gpm cups samba asusoled-clockd bluetooth transmissiond sshd)
i know there is an order for some things, i just dont know what, so my question, is my order ok? if not what do i need to switch?
thanks

adamruss wrote:
Inxsible wrote:
adamruss wrote:
i have a question about the deamon array in rc.conf, this is mine:
DAEMONS=(preload syslog-ng dbus acpid netfs alsa crond hal acpi-support fam stbd wicd gpm cups samba asusoled-clockd bluetooth transmissiond sshd)
i know there is an order for some things, i just dont know what, so my question, is my order ok? if not what do i need to switch?
thanks
As long as the daemons are independent of each other, it hardly matters what order they are started in. The only thing is that the syslog-ng is used for logging...so you always want to start that before anything else so that in case there are errors in starting any daemon, they will logged and you can see them later.
I am not sure what 'preload' daemon is. Also you might want to start the unimportant ones in the background by prefixing them with an '@' sign so that your boot up would be quicker.
what do you mean unimportant?
You could bacground "alsa gpm cups samba bluetooth".
Oh, and if you don't use any network filesystems remove netfs. Don't have any cronjobs remove crond.

CAS (array) questions redux

I have a single Exchange server, where Get-Mailboxdatabase reports that the RPCClientAccessServer is servername.domain.local
I'm currently having a certificate mismatch due to using a wildcard certificate, this only manifests as an error popup when you first start Outlook. Mail works fine, as do calendars - but I want to get rid of that pop-up.
I'm already doing a split-brain DNS for EWS and so forth - mail.domain.com resolves to an internal IP internally and an external IP externally through a "real" DNS entry that's Internet-facing, and this way neither users internally or externally
get certificate errors and everything works - EAS, OWA etc. So it's just this internal issue left.
The question I have is that I read something about it being a bad idea to use the same DNS name for CAS if the same address is externally resolvable (which it would be in this case). Does setting RPCClientAccessServer affect external clients too?
Should I create a second split brain DNS entry instead, like mail-internal.domain.com and point that at servername.domain.local just to use for CAS?
The second part of this question - can I just do: Set-MailboxDatabase MailboxDatabaseName -RpcClientAccessServer “mail.domain.com” and walk away, ie skip the CAS array creation entirely if I were to choose that, assuming mail.domain.com resolves internally
to servername.domain.local?
Or should I definitely create the array and use that instead even though this is a single-server environment?
Thanks.

Indeed!
http://blogs.technet.com/b/exchange/archive/2012/03/23/demystifying-the-cas-array-object-part-1.aspx is what Will is referring to.
No, it is not that simple of just changing it and walking away.
Is this Outlook 2013 by any chance?
Cheers,
Rhoderick
Microsoft Senior Exchange PFE
Blog:
http://blogs.technet.com/rmilne
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Note: Posts are provided “AS IS” without warranty of any kind, either expressed or implied, including but not limited to the implied warranties of merchantability and/or fitness for a particular purpose.

Quick Array Question

Hey,
I was wondering if you folks could help me.
I am going to use arrays for this program, but I can�t seem to get the first point right, it just won�t compile.
Any who...My goal here is to create a program that prompts the user for the number of tests, then the program loops the desired amount of times, each loop the user will be prompted for the student id, name, test score...etc using arrays.
My question is...first off, how do I get it to start...lol, and secondly, how do I input various amounts of strings (i.e. names) into an array...then output them latter. Here is my code thus far.
import javax.swing.JOptionPane;
public class TestScoreFinal {
     public static void main(String[] args){
          // Declarations
          String numTest;
          String testScore;
          double nTest;
          double tScore;
          // Input of Number of Tests
          double[] totTests;
          int numTest = readInt("Enter the Number of Tests ");
          totTests = new double[numTest];
          // FOR loop, will stop when it is equal to the number of tests inputed
          for(int countTest = 0; countTest < nTest; countTest = countTest + 1){
               testScore = JOptionPane.showInputDialog("Please Enter a Test Score: ");
               tScore = Double.parseDouble(testScore);
               // If number is less than zero, the loop ends
               if (tScore < 0){
                    JOptionPane.showMessageDialog(null, "Invaild Test Score!, No Results will be Shown!");
                    break;
               // If Number is greater than 100, the loop ends
               else if (tScore > 100){
                    JOptionPane.showMessageDialog(null, "Invaild Test Score!, No Results will be Shown!");
                    break;
               // If Test score is Valid, we proceed to the Calculations
               else
}I get the following errors...
--------------------Configuration: <Default>--------------------
C:\Documents and Settings\**** ****\Desktop\Hand In\TestScoreFinal.java:17: numTest is already defined in main(java.lang.String[])
int numTest = readInt("Enter the Number of Tests ");
^
C:\Documents and Settings\**** *****Desktop\Hand In\TestScoreFinal.java:17: cannot find symbol
symbol : method readInt(java.lang.String)
location: class TestScoreFinal
int numTest = readInt("Enter the Number of Tests ");
^
C:\Documents and Settings\**** ****\Desktop\Hand In\TestScoreFinal.java:18: incompatible types
found : java.lang.String
required: int
totTests = new double[numTest];
^
3 errors
Process completed.

I lied..god im stupid...final question...
import javax.swing.JOptionPane;
public class TestScoreFinal {
     public static void main(String[] args){
          // Declarations
          int numTest;
          String names;
          String testScore;
          double nTest;
          double tScore;
          // Input of Number of Tests
          double[] totTests;
          String num = JOptionPane.showInputDialog("Enter the Number of Tests");
          numTest = Integer.parseInt(num);
          totTests = new double[numTest];
          // FOR loop, will stop when it is equal to the number of tests inputed
          for(int i = 0; i < totTests.length; i++){
               testScore = JOptionPane.showInputDialog("Please Enter a Test Score: ");
               tScore = Double.parseDouble(testScore);
               String names = JOptionPane.showInputDialog("Enter the Students Name: ");
               String[] name = new String[names];
               // If number is less than zero, the loop ends
               if (tScore < 0){
                    JOptionPane.showMessageDialog(null, "Invaild Test Score!, No Results will be Shown!");
                    break;
               // If Number is greater than 100, the loop ends
               else if (tScore > 100){
                    JOptionPane.showMessageDialog(null, "Invaild Test Score!, No Results will be Shown!");
                    break;
               // If Test score is Valid, we proceed to the Calculations
               else
}what did i do wrong here? im pretty sure it should be working!
--------------------Configuration: <Default>--------------------
C:\Documents and Settings\********Desktop\Hand In\TestScoreFinal.java:30: names is already defined in main(java.lang.String[])
String names = JOptionPane.showInputDialog("Enter the Students Name: ");
^
C:\Documents and Settings\********\Desktop\Hand In\TestScoreFinal.java:31: incompatible types
found : java.lang.String
required: int
String[] name = new String[names];
^
2 errors
Process completed.

[SOLVED] Daemons Array Question

Two questions, actually:
1) When I installed wicd, the Arch Wiki told me to disable the network daemon with "!network". What is the difference between using the exclamation mark and just removing the word "network" from the array?
2) From what I can tell, netfs is used to access files on a network, like a LAN, correct? If I don't use that functionality on my laptop, is there any reason to keep this daemon at all? (i.e. does it have any effect on my internet access?)
Last edited by dfetter88 (2010-06-15 03:32:50)

1) When I installed wicd, the Arch Wiki told me to disable the network daemon with "!network". What is the difference between using the exclamation mark and just removing the word "network" from the array?
Nothing really.
2) From what I can tell, netfs is used to access files on a network, like a LAN, correct? If I don't use that functionality on my laptop, is there any reason to keep this daemon at all? (i.e. does it have any effect on my internet access?)
That's right. It will mount the network locations from your /etc/fstab

Help: array question

Hi:
I have a question concerning character arrays?
Given a string of letters, how would I find the postion of the letter in the array?
Thanks.

     String arr = "abcdefg";
     char[] charr = arr.toCharArray();
     for(int j = 0 ; j < charr.length; j++) {
      if(charr[j] == 'e') {
       int postion = j;
       System.out.println("The postion of"+" " + charr[postion] + " " + "is in the" +" " + postion + " " + "cell of charr");
    }Is this what you are looking for ???

Queue vs. Array question

I had a recent application where I wanted to take 100 samples of something then get the RMS of the dara. This happens in a loop and until program ends. Very basic stuff.
QUEUE Method:
Obtain Queue with 100 elements max.
Enqueue data (data arrives about every 50mS).
Get Queue Status, when Number of Elements is 100....
... Flush Queue and get all elements (that'll be an aray of course) and use RMS funtion.
Repeat
ARRAY Method:
Initialize Array with 100 elements of the DBL 9999.99 (that's a value that can't occur in the data)
Insert data into the array by using Replace Array Subset
When index 100 is not 9999.99, then....
... Put array in the RMS function, then re-initialize array full of 9999.99
Repeat
So my questions are, which should be Faster, which one better Memory Management ?
Thanks!
Solved!
Go to Solution.

LV_Addict wrote:
I had a recent application where I wanted to take 100 samples of something then get the RMS of the dara. This happens in a loop and until program ends. Very basic stuff.
QUEUE Method:
Obtain Queue with 100 elements max.
Enqueue data (data arrives about every 50mS).
Get Queue Status, when Number of Elements is 100....
... Flush Queue and get all elements (that'll be an aray of course) and use RMS funtion.
Repeat
ARRAY Method:
Initialize Array with 100 elements of the DBL 9999.99 (that's a value that can't occur in the data)
Insert data into the array by using Replace Array Subset
When index 100 is not 9999.99, then....
... Put array in the RMS function, then re-initialize array full of 9999.99
Repeat
So my questions are, which should be Faster, which one better Memory Management ?
Thanks!
Queues can pass data "inplace" by just moving the pointer to the data buffer to who ever want to read the queue.
The array method you outlined requires repeatedly peeking in at the data buffer to decide what you need to do plus you have to over-write the buffer with you special "code".
Ben
Ben Rayner
I am currently active on.. MainStream Preppers
Rayner's Ridge is under construction

Some basic HP Smart Array questions

Hopefully a simple answer to what seems to be a fairly simple question...
If, for example, you have a P800 HP Smart Array with 24 disks and a spare and you want to partition a number of database files across drives to maximise I/O performance (the transaction log file is heavy on writes and the other data and index files are heavy on reads), would it be better to:-
a) Use the 24/25 disks to create one SAS Array and three logical drives:-
SAS Array A with spare - 3 Logical drives
     Logical Drive 1 (1200 Gb, RAID 1+0)
     Logical Drive 2 (1200 Gb, RAID 1+0)
     Logical Drive 3 (1200 Gb, RAID 1+0)
b) Use the 24 disks to create three SAS arrays each with one Logical Drive:-
SAS Array A & Logical Drive 1  (1200 Gb, RAID 1+0)
SAS Array B & Logical Drive 1 (1200 Gb, RAID 1+0)
SAS Array C & Logical Drive 1  (1200 Gb, RAID 1+0)
Not sure how the Spare disk fits into Option B?
Anyway, if the objective is to maximize I/O performance, is it Option A or B?
The phrase, 'logical drive'... Does this mean that I/O is partitioned at the logical drive level or does the HP Smart array controller spread the I/O across the SAS Array? If I look at I/O counters (eg. Perfmon on Windows Server), I can see that Logical drives as in Option A seem to be separated completely as one logical drive could have a disk queue and other logical drives on top of the same SAS array will not have a disk queue.  What are the prose and cons of Option A and B? Understanding these issues will help me to come up with the right configuration in terms of arrrays and logical drives.
Thanks in advance,
Clive

Hi, Clive:
I'm not so sure yours is a fairly simple question for the HP consumer notebook forum.
You may want to copy and paste your post in the HP Business Support Forum -- Disk Array section.
http://h30499.www3.hp.com/t5/Disk-Array/bd-p/itrc-195

Associative Array Question

Hi All,
I've searched through this forum trying to find information I'm needing on associative arrays with a varchar2 index without luck. What I'm looking for is a way to get the index or "key" values of the array without knowing what they are. Meaning, I wouldn't have to know the index value when designing the array but would be able to utilize them values at runtime. For those familiar with Java it would be like calling the keySet() method from a Map object.
So, if I have an array of TYPE COLUMN_ARRAY IS TABLE OF VARCHAR2(4000) INDEX BY VARCHAR2(100) is there any way to dynamically get the index values without knowing what they are?
Any help is appreciated.
Thanks

Thanks for the response.
I am aware of using FIRST and NEXT for iterating the array but can I extract the index value of the current element into a variable when I don't know what the index value is at runtime ?
Thanks

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