Length of 2d arrays

If I have this array specified:
String[][] myArray = new String[5][10];Is there a way to use the ".length" variable to get both the "lenght" and the "width" (5 and 10) for this array? It's awefully handy with regular 1D arrays, but I'm getting a little confused with the 2D arrays.

Sure, myArray.length is the length of the "outer"
array. Since that outer array is just an array of
other arrays, you take an arbitrary position, and
find it's length.
myArray[0].length gives the length of the first
"inner" array. Keep in mind that all of the inner
arrays don't necessarily have the same length.YES! Thank you! I knew there had to be some way to do this, but I couldn't figure it out.
As it stands, the arrays I'll be working with are not ragged, so this should work quite well.
Thanks!

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Length variable in arrays

When we use the neew operator to make an array which method is called by the new operator and the length variable in arrays resides in which class

What?

Where will be the length property of Array will lie in JAVA API

where will be the length property of Array will lie in JAVA API

sandeepmalladi wrote:
where will be the length property of Array will lie in JAVA APIThere is no length property of Array. As to where you find a definition of the length field of an array, it's in the [Java Language Specification|http://java.sun.com/docs/books/jls/third_edition/html/arrays.html].
~

Länge eines Array (length of an array)

Hallo,
gibt es ähnlich wie bei Kanälen - chnlength - eine Möglichkeit die Länge von Arrays abzufragen?
Is there any possibility to get the length of an array like chnlength?
Gruß

Arrays in vbs are a little tricky.
Thats mainly because
dim arr()
does not create an empty array but an unitialized one. So calling Ubound(arr) will raise an error.
It will also fail to loop using "for each".
So I would suggest to never use "()" to define an array but
dim arr : arr = Array()
MsgBox "length=" & ubound(arr) + 1
dim arrElem
for each arrElem in arr
' here we can do something
Next
Array() will create an initialized Array of length 0. UBound will give -1 as return value.
Usng this returing an array from a funtion works quiet well without having to check for exceptions if array is empty.
Option Explicit
Function GetElems()
GetElems = Array()
' do some stuff
end function
dim elems : elems = GetElems
dim elem
for each elem in elems
' here we can do something
Next
If you want to dynamically grow an array you can use redim preserve.
Option Explicit
dim arr : arr = Array()
redim preserve arr(Ubound(arr) + 1)
arr(UBound(arr)) = "Appended text"
MsgBox "length=" & ubound(arr) + 1 & VBCRLF & arr(0)

How can I know the length of an array in the class?

hard to express, I show guys an example:)
public class code{
pblic String[] str; // String array
public test () {
// I hope to print all items in the array after initiation;
// e.g. if String[3] , then print str0, str1,str2; if String[4], then //print str0, str1, str2, str3;
My puzzle here is, since the "str" may be not the same length in different initiation of code object, how can I implement the test method to print all items

for (int i = 0; i < str.length; i++)
System.out.println(str);

Max length of G_F array

I have a html table on a APEX page. User can add/delete rows from the table at run time. I use attribute name="Fxx" to name input fileds. For example, name="F05" for the text_area inputs in column 5. When the page is submitted, I capture the values by loop through array apex_application.g_f05.
Everything works fine until I have more than 475 rows in the table. IE gives me a "Page can't be displayed" error when submit.
My question is: Is there a max length of apex_application.g_fxx type array? Have I reached the plsql limitation or apex_application.g_fxx limitation? How can resolve this?
Thanks.

I need to allow submit upto 700 rows from a html table on a APEX page. But what I have encountered is that if I have less that 478 rows in the table, there is no problem to submit the page and save all data to database. But as soon as I have more than 478 rows on the table, the submission will fail and the browser simply display a 'Page cannot find " error.
Has anybody experieneced this before? Is there a way to resovle this? Thank you.

To get a real length of an array

if there is an array not full,how do i calcuate how many elements in an array are??
for example:
ARRAY A={"A","B","NULL","NULL"};
HOW TO FIND THE LENGTH IS "TWO"
THANKS IN ADVANCE

String[] a = {"a", "b", "null", "null"};
has length four as well as having four filled Strings in it.
however..
String[] a = new String[4];
a[0] = "a";
a[1] = "b";
and you want to find out that there are two in it?
then count like r.klemme said.
int count =0;
for (int i=0;i<a.length;i++) {
if (a[i] != null) count++;
System.out.println("array " + a + " has length=" + a.length + " with " + count + "units in it");

Length variable in array

Can anybody tell me where(class/interface/enum) is variable 'length' defined?
In int[] intArray = {9, 99};
System.err.println(intArray.length); Returns 2.
Thanks

Go throgh java.lang.reflect.Array
It has public static Object newInstance(Class<?> componentType, int length) and public static native int getLength(Object array) getLength(Object array) is a native method, it returns lenth of the array.

Limit to length of dash arrays

I've not been able to find any documented limit to the number of elements in a line dash pattern, but Adobe Reader seems to refuse to read a PDF file if the number exceeds 10. Is this the limit or does it depend upon something else (such as the dash lengths for example)?

This is documented in the PDF Reference in the Implementation Limits section - and yes, the current limit as implemented by Adobe Reader/Acrobat is 10.
Leonard

Getting a C variable length array

Hello,
I'm working on a DLL library. One of the functions should return to LabView a lot of data.
By the moment I'm doing something like this (using 'by reference' parameters):
int getDataFromC(int* data1, char* data2, double* data3);
The function returns an error code, which is used to know everything goes fine. The memory of each parameter is allocated by LabView when it calls the library function. In C, the function doesn't allocate memory, it just copy the information to the space allocated by LabView (*data1 = xxx. Then LabView uses it by reading each parameter. It works fine.
The problem is that part of the data that comes from the DLL are arrays. These arrays are generally variable length arrays. Each array always comes with other value, which describes the length of the array. So the returned array can change its length.
By the moment I'm assuming LabView allocates enough memory to let the C code writes all the array data. But it's not a good practice...
For example:
int getArrayFromC(int* len, int array[]);
The C code writes the length value to the '*len' variable to inform LabView the size of the array, and writes the N ints to the array (assuming there is enough space allocated by LabView).
What's the array's length that LabView uses in this case?
On the other hand, I'd prefer to use something like:
int getArrayFromC(int* len, int* array[]);
In this case I can control the length of the array. It is a array-by-reference situation. I could change the array used by LabView.
What do you recommend? I just need to get a variable length array.
Thanks!
Mauricio

LabVIEW allocates as much memory for an array as is needed. They are always variable length, as LabVIEW dynamically resizes the array if you add to it. However, when you call a DLL, the DLL cannot tell LabVIEW to increase the size of the array as it builds it. So, the array needs to be large enough for the DLL to fill it up, or you could cause memory corruption/crashing.
Depending on how your DLL has been written, you may be able to use the DLL to help you. A lot of times, you specify the length as an input with the array, and the DLL checks to see if you have enough memory allocated. If not, then the call generates an error, and the output of the len input is how big an array is needed. So, you make a call with a size that typically is going to be large enough, and check for the error. If you get the error, then you resize your LabVIEW array, and call the function again to get all the data. Another option is to always call it with 0 elements, knowing you will get an error, then allocate the array.
If the DLL has not been written to verify you have specified enough memory, then you need to allocate an array you believe is big enough.

Array Length?

the length property of an array object is final. How is it then possible to create an array object at run-time and specify the length for the array?
Thanks in advance

public myClass {
public final int myValue;
myClass(int value) {
myValue = value;
//rest of your constructor code...
//rest of your class
The key is you have to set the value of the final 'variable' in your constructor. which means, unless the value is calculated in the constructor, it should be passed to the constructor like:
myClass mc = new myClass(1400);
Steve

Passing Array to Alchemy, Array.length

Hi,
Trying to pass an Array to alchemy. Works great, but...
How to determine length of the array?
My code (ahum :-) thus far:
static AS3_Val test(void* self, AS3_Val args)
AS3_Val dataVal = AS3_Undefined();
AS3_ArrayValue( args, "AS3ValType", &dataVal );
// trace out array[0]
AS3_Trace( AS3_Get(dataVal, AS3_Int(0) );
return AS3_Null();
Thanks,
Tim

To answer my own :
1] maybe smarter to pass length of array too :-)
2] do a loop:
int len = 0;
while( AS3_Get(arrayVal, AS3_Int(len++)) )
Guess this is _not_ the way to do it, but at least seems to
work

Finding Array Length

I was just wondering if i have an array
double [][][] array = new double [1][2][3];array.length only gives 1, what function can i use to find the size of the other dimensions (2 and 3)? Thanks in advance for any help.

I'll try and explain this a little better.
Say array[0].length is 2, then that means that there is only
array[0][0] and array[0][1].
If array[0][0] is 4, then that means that there is only
array[0][0][0], array[0][0][1], array[0][0][2], and array[0][0][3].
The reason i did array[0][0].length and not array[0][1].length
in my other post is because they would both return the same
thing because of the way you declared the array.
When you dodouble[][] array = new double[2][3];this is making it so that array[0].length is 3 and array[1].length is 3.
But if you do this (shown in the previous post)
double[][] aray = {
{ 2.4, 5.6, 6.4 },
{ 1.4 }
}then array[0].length is 3, but array[1].length is 1.
Hope this helps.

I am trying to create N random arrays of a given length help please!

Hi,
I was given this picture last week as a block diagram in order to create N arrays of a specified length M. The array is to have a floating point representation (i.e. the values that make up the array of numbers can be anything specified by myself.
I attach the picture here and was wondering if someone could tell me what the block diagram object to the right of the random number block diagram object is and where I can find it in LabVIEW, also the block diagram object underneath "N random arrays".
Thanks, This picture is from LabVIEW v.6.1, I am using LabVIEW v.7.1.
Alan Homer
Message Edited by alanhomer on 03-21-2006 03:28 AM
Attachments:
N random arrays.png ‏5 KB

Hi Alan,
The function you want is a bundle found on the cluster palette. You need to make the bundle smaller as it comes off the palette with 2 input.
I attach a VI that is a match to the image you sent, this contians everything wired together and should work out of the box.
Regards
JamesC
NIUK and Ireland
Attachments:
alanhomer.vi ‏20 KB

How to know the length of a Byte array?

how to know the length a byte array if it is an argument of the method, e.g.
public byte[] hash(byte[] data) throws Exception
I wanna store the length of data into a integer in the method of hash, but no idea how to get it
THanks!

to conclude:
I am a newbie, I wanna know , those "System"
methods as well.What exactly does that have to do with your original question?
or instance:
System.arrowcopy() , where can I find the
definition also?You probably meant System.arraycopy. The documentation is called JavaDoc and for Java 1.5 (a.k.a. 5.0) it can be found here: http://java.sun.com/j2se/1.5.0/docs/api/index.html
If you've not yet found the API documentation, then I'm pretty sure you should start with some tutorials, they probably point to all the interesting documentation as well.

Length of 2d arrays

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