Wadi Hanifa

Wadi Hanifa (Arabic: وادي حنيفة‎‎) is a wadi or valley in the Nejd region, Riyadh Province, in central Saudi Arabia. The valley runs for a length of 120 km (75 mi) from northwest to southeast, cutting through the city of Riyadh, the capital of Saudi Arabia. A string of towns and villages lie along the valley, including Uyaynah, Irqah and Diriyah. The historical city of Riyadh itself is on the northeastern side of the wadi, but the city has now expanded across Wadi Hanifa, with the sub-municipalities of Al-Shifa and Al-Urayja on its southwestern side.

In pre-Islamic Arabia, the wadi was known as al-Irdh العرض. Its current name is derived from that of the Banu Hanifa, the principal Arab tribe in the area at the time of the Islamic conquest of Arabia.

Images:

There are six open parks, which are Sud Al-Elb Park, Sud Wadi Hanifa Park, and Bio Treatment Park in Otaiqah, Sud Park, Factories Lake Park and Lake Park

Coordinates:  24.570396, 46.723286

Images:

Mobily 4G LTE Router Unlock for All SIM Cards

Mobily 4G LTE Router Unlock for All SIM Cards

How to Openline / Unlock Mobily 4G LTE Router (Tutorial)

Steps:

·         First take out your SIM Card to avoid problem during firmware upgrade

·         Download this 3 file (Firmware upgrade).

1. link 1 
2. link 1 
3. link 1 

1.  ·         Go to Log in page http://192.168.2.1 (Default Password)

·         Follow steps Picture below (Firmware Upgrade)

·         Router will restart after upgrade is complete

·         Wait count down timer as you see above

·         After that go here

·         Then click LTE Module Upgrade (last line)

·         Follow screen shot below

·         Router will retart again after Update is complete

·         Then click Adv. Settings

·         Now we will proceed to SIM LOCK removing

·         Follow screen shot

·         (Optional) Same as STEP 2! just choose  mr7015al-zz_r0b_FW_1.02.33(20120618).bin

·         Last step: Changing APN

·         Click LTE/UMTS (Follow screen shot below)

·         Click Apply

·         Done!

Xamarin Mono For Android 4.12 installation, crack

The original: http://hi.baidu.com/hegel_su/item/2b0771c6aaa439e496445252?qq-pf-to=pcqq.group

1 installation environment introduction:

Win8.1 Enterprise Edition 64, VS2013, mono-android-4.12.02001, the installation process below are successfully has been installed in the VS2013 operation, the support of vs2013 Chinese crack.

Installing JDK 2

To Oracle official download and install jdk-6u45-windows-i586.exe

Add the environment variable JAVA_HOME

C:\Program Files (x86)\Java\jdk1.6.0_45

Add the environment variable CLASSPATH

.;%JAVA_HOME%\lib\dt.jar;%JAVA_HOME%\lib\tools.jar

Modify the environment variable Path, add the following values at the front:

.;%JAVA_HOME%\bin;%JAVA_HOME%\jre\bin;

3 installation Android SDK, download the installer_r22.6.2-windows.exe, I am here is mounted to the D:\Develop\Android\android-sdk directory

Can also download the offline package, unzip to D:\Develop\Android\android-sdk, installer_r22.6.2-windows.exe toinstall to install the latest version of the unpacked

After the installation to set environment variables, right-click My Computer properties -- -- -- -- advanced system settings advanced environmental variables -- variables, find the Path, click Modify, increase in the front:

D:\Develop\Android\android-sdk\tools;D:\Develop\Android\android-sdk\platform-tools;

(note must end with semicolon; English, if Path has the value, it is not necessary to add, if it is mounted to the other directory, corresponding to modify the path)

4 in order to download and install the following software:

1)gtk-sharp-2.12.25.msi

2)XamarinStudio-4.2.3.60-60.msi

3)XamarinInstaller.exe, Automatic installation of NDK, Android and iOS plugin (can also be used manually installed sequentially installed)

After the 5 best all finished, restart the computer

6 Download Windows following patch:

1)Crack Android: copy mandroid.exe to%PROGRAMFILES(x86)%\MSBuild\Xamarin\Android

The switch in the CMD command to%PROGRAMFILES (x86)%\MSBuild\Xamarin\Android directory, run the following command register:

mandroid.exe --activate --activation-name=b4a --activation-phone=b4a --activation-company=b4a --activation-code=b4a --activation-email=b4a

Check whether the registration is successful

Run command: mandroid.exe --entitlements > "%temp%"\mfa.txt

Then run the command: type "%temp%"\mfa.txt

If appear similar to " xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx MonoAndroid Priority2014-08-26T05:52:36" form that is registered successfully.

2)Crack iOS: copy mtouch.exe to%PROGRAMFILES(x86)%\MSBuild\Xamarin\iOS

The switch in the CMD command to%PROGRAMFILES (x86)%\MSBuild\Xamarin\iOS directory, run the following command register:

mtouch.exe --activate --activation-name=b4a --activation-phone=b4a --activation-company=b4a --activation-code=b4a --activation-email=b4a

With part of the original procedure download address:

http://dl.google.com/android/installer_r22.6.2-windows.exe

http://dl.google.com/android/ndk/android-ndk-r8d-windows.zip

With Android SDK development kit the download address:

Part of the original address from the following contents:

Two, Mac the following installation

Installing Max 1, this is not to say, the reference article

http://hi.baidu.com/hegel_su/item/421ee407956898b03c42e20e

Install the Xcode procedure in the above article, pay attention to, if you want to use under the MAC simulator, it can only be installed 5.0.2 Xcode, if only the prototype debugging, you can install the Xcode 5.1

Installing Xamarin 2, to the official website to download online setup XamarinInstaller.dmg for automatic installation, the installation process to download a file, so this step will be a bit long, waiting for the automatic installation is completed, the automatic installation program download address:

3 automatically after the installation of the version is not broken, and is compared with the old version, we next to the corresponding version download crack, download the following all the linked files, and in order to install:

1)

2)

3)

4)

To download files:

Solving steps are as follows:

a) replace mtouch in /Developer/MonoTouch/usr/bin/

b) replace mandroid in /Developer/MonoAndroid/usr/bin/

c) Executed on the command line: sudo chmod a+x /Developer/MonoAndroid/usr/bin/mandroid

d) Run in Cmd: /Developer/MonoAndroid/usr/bin/mandroid --activate --activation-name=b4a --activation-phone=b4a --activation-company=b4a --activation-code=b4a --activation-email=b4a

e) Run in Cmd: /Developer/MonoAndroid/usr/bin/mandroid --entitlements

If the output is similar to " xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx MonoAndroid Priority2014-08-26T05:52:36" said success

f) execute: /Developer/MonoTouch/usr/bin/mtouch --activate --activation-name=b4a --activation-phone=b4a --activation-company=b4a --activation-code=b4a --activation-email=b4a

Infragistic Ultra Grid Formatting Code

code for displaying delete conformation 

  Dim row As UltraGridRow

                If CSMsgBox.ShowQuestionMessage("Do you want to delete the data on the grid?", MessageBoxButtons.YesNo) = Windows.Forms.DialogResult.Yes Then

                    For Each row In Me.UltraGrid1.Selected.Rows

                        row.Delete(False)

                        Me.UltraGrid1.UpdateData()

                    Next

                End If

code for displaying checkbox and text after check box click in ultra grid

 Dim chk As New Infragistics.Win.UltraWinEditors.UltraCheckEditor

 Me.UltraGrid1.DisplayLayout.Bands(0).Columns("ACTIVE").Style = ColumnStyle.CheckBox

        Me.UltraGrid1.DisplayLayout.Bands(0).Columns("ACTIVE").Editor = chk.EditorUltraGrid1.DisplayLayout.Bands(0).Override.CellDisplayStyle = CellDisplayStyle.FormattedText

Ultra Grid: Remove/Change selected Row color

If you want to remove selected row color(by default blue) and preserve your cell colors, follow this procedure.

Private Sub grid1_InitializeLayout(ByVal sender As System.Object, ByVal e As Infragistics.Win.UltraWinGrid.InitializeLayoutEventArgs) Handles ultragrid.InitializeLayout

'Make selected row color to transparant
e.Layout.SelectionOverlayColor = SystemColors.Highlight
'remove slected and active appearance
With e.Layout.Bands(0)
.Override.SelectedAppearancesEnabled = DefaultableBoolean.False
.Override.ActiveAppearancesEnabled = DefaultableBoolean.False
End With

End Sub

code for Auto_fitting columns to ultraGrid's width

first of all import this

Imports Infragistics.Win.UltraWinGrid

Then

Me.UltraGrid1.DisplayLayout.AutoFitStyle = AutoFitStyle.ResizeAllColumns

code for Ultra Grid to select an entire row when a cell is clicked

UltraGrid1.DisplayLayout.Override.CellClickAction = Infragistics.Win.UltraWinGrid.CellClickAction.RowSelect

code for Ultra Grid, how to lock cell data - disable editing

' Disable updating on the entire grid
Me.ultraGrid1.DisplayLayout.Override.AllowUpdate = DefaultableBoolean.False


' Enable updating on the root band. This will override the DisplayLayout setting
Me.ultraGrid1.DisplayLayout.Bands(0).Override.AllowUpdate = DefaultableBoolean.False

Code for Multi selection off
 e.Layout.Override.SelectedAppearancesEnabled = DefaultableBoolean.False

If u want on then simply write true in place of false on above line

Code for ADD New Row
if you want at row on buttom then do this
UltraGrid.displaylayout.Override.AllowAddNew=AllowAddNew.FixedAddRowOnBottom

if you want at row on top then do this
UltraGrid.displaylayout.Override.AllowAddNew=AllowAddNew.FixedAddRowOnTop

and so on many properties please explore it

Code for Row Selector
Me.UltraGrid.displaylayout.Bands(0).Override.RowSelectors=DefaultableBoolean.True


Code for delete row from database

Me.UltraGrid.ActiveRow.Delete()

Code for Color the specific column
 in ultragrid InitializeRow event
  e.Row.Cells("cell name here").Appearance.BackColor = Color.Green


Code for Hide row selectors:

in ultragrid InitializeLayout event
e.Layout.Override.RowSelectors = DefaultableBoolean.False

Code for Column Sorting Disable

in ultra grid Initialize Layout event

e.layout.Override.HeaderClickAction = HeaderClickAction.Select
e.layout.Override.SelectTypeCol = SelectType.None


Hide group header box:
In ultra grid grid Initialize Layout

e.Layout.GroupByBox.Hidden = True

code for Hide row selectors:
In ultragridgrid InitializeLayout event

e.Layout.Override.RowSelectors = DefaultableBoolean.False

 three properties of the override that control

 ' on the Override off the DisplayLayout, then these settings apply to the whole

      ' UltraGrid.

  'FOR MODIFY  ALLOW OR UPDATE IN ULTRAGRID

      Me.ultraGrid1.DisplayLayout.Override.AllowUpdate = DefaultableBoolean.True

'FOR adding and delecting in ultragrid

      Me.ultraGrid1.DisplayLayout.Override.AllowAddNew = AllowAddNew.No

      Me.ultraGrid1.DisplayLayout.Override.AllowDelete = DefaultableBoolean.False

     ' You can set them on a specific band as well. These settings override those

      ' set on the DisplayLayout's Override object for this band.

   Me.ultraGrid1.DisplayLayout.Bands(0).Override.AllowUpdate = DefaultableBoolean.True

      Me.ultraGrid1.DisplayLayout.Bands(0).Override.AllowAddNew = AllowAddNew.No

      Me.ultraGrid1.DisplayLayout.Bands(0).Override.AllowDelete = DefaultableBoolean.False

 ' There are Activation properties on row, column and cells that dictate whether

      ' associated cells can be modified, or can even enter in edit mode.

  Dim column As UltraGridColumn = Me.ultraGrid1.DisplayLayout.Bands(0).Columns("CustomerID")

      Dim row As UltraGridRow = Me.ultraGrid1.Rows(0)

' Set the CellActivation off the column something other than AllowEdit to prevent

  ' the user from modifying cells in that column. ActivateOnly allows the user to

  ' go into edit mode so the user can select and copy text, however the cell will

      ' be read-only thus preventing any data modification.

      column.CellActivation = Activation.ActivateOnly

      ' You can override cell activation setting for a particular row.

      row.Activation = Activation.ActivateOnly

      ' Furthermore you can override activation on a cell as well.

      row.Cells(column).Activation = Activation.AllowEdit

 code for Selecting single row:
In ultragridgrid InitializeLayout event

e.Layout.Override.SelectTypeRow = Infragistics.Win.UltraWinGrid.SelectType.Single

code for made Fixed Columns
In ultragridgrid InitializeLayout event

e.Layout.UseFixedHeaders = true
UltraGrid.Bands[0].Columns[0].Header.Fixed = true
UltraGrid.Bands[0].Columns[1].Header.Fixed = true
                               OR
Me.UltraGrid.displaylayout.override.AllowCalSizing=AllowCalSizing.None

code for made Fixed Row
Me.UltraGrid.displaylayout.override.RowSizing=RowSizing.Fixed

Change cell button properties/appeacence
In ultragridgrid InitializeLayout event

e.Layout.Bands(0).Columns("name of cell write here").CellButtonAppearance

code for Disable Column Sorting
In ultragridgrid InitializeLayout event


e.Layout.Override.HeaderClickAction = HeaderClickAction.Select
e.Layout.Override.SelectTypeCol = SelectType.None

code to enable immediate scrolling

In ultragridgrid InitializeLayout event

e.Layout.ScrollBounds = ScrollBounds.ScrollToFill
e.Layout.ScrollStyle = ScrollStyle.Immediate


code  for Update datasource for each cell change
In ultragridgrid InitializeLayout event

UltraGrid1.UpdateMode = Infragistics.Win.UltraWinGrid.UpdateMode.OnCellChange

code if you want To change grid Header Appearance
In ultragridgrid InitializeLayout event

UltraGrid1.DisplayLayout.Bands(0).Override.HeaderAppearance property

code if you want To disable column swapping, moving,sizing and GroupBy
In ultragridgrid InitializeLayout event

With UltraGrid1.DisplayLayout.Bands(0).
.Override.AllowColMoving = AllowColMoving.NotAllowed
.Override.AllowColSwapping = AllowColSwapping.NotAllowed
.Override.AllowColSizing = AllowColSizing.None
.Override.AllowGroupBy = DefaultableBoolean.False


code for Show header text in multi line

In ultragridgrid InitializeLayout event


UltraGrid1.DisplayLayout.Bands(0).Override.WrapHeaderText = DefaultableBoolean.False
UltraGrid1.ColHeaderLines = 2 'two lines
UltraGrid1.Columns(0).Header.Caption = "here write text" & Environment.NewLine & "here write text"


code to select a full row if click on any cell
In ultragrid InitializeLayout event

UltraGrid1.DisplayLayout.Bands(0).Override.CellClickAction = CellClickAction.RowSelect

code for Hide a column
In ultragrid InitializeLayout event
UltraGrid1.DisplayLayout.Bands(0).Columns("here write column name").Hidden = True


code for Adding DropDownList column
In ultragrid InitializeLayout event


UltraGrid1.DisplayLayout.Bands(0).Columns("here write ColumnName").Style = ColumnStyle.DropDownList
UltraGrid1.DisplayLayout.Bands(0).Columns("here write ColumnName").ValueList = UltraGrid1.DisplayLayout.ValueLists("my list")

' now create ultragrid list
UltraGrid1.DisplayLayout.ValueLists.Add("my list")
UltraGrid1.DisplayLayout.ValueLists("my list ").ValueListItems

Dim list As New ValueListItem()

list.DataValue = 1
list.DisplayText = "car"
.Add(list)

list= New ValueListItem()
list.DataValue = 2
list.DisplayText = "bus"
.Add(list)

list= New ValueListItem()
list.DataValue = 3
list.DisplayText = "train"
.Add(list)


list= New ValueListItem()
list.DataValue = 4
list.DisplayText = "motor cycle"
.Add(list)



code for Adding a button column
In ultragrid InitializeLayout event

UltraGrid1.DisplayLayout.Bands(0).Columns(0).Style = ColumnStyle.Button
UltraGrid1.DisplayLayout.Bands(0).Columns(0).ButtonDisplayStyle = UltraWinGrid.ButtonDisplayStyle.Always


code for make cell text multi line
In ultragridgrid InitializeLayout event

UltraGrid1.DisplayLayout.Bands(0).Columns(0).CellMultiLine = DefaultableBoolean.True


UltraGrid1.DisplayLayout.Bands(0).Columns(0).VertScrollBar = True

code for reset the sorted columns when unloading
ultraGrid1.DisplayLayout.Bands[0].SortedColumns.Clear()

Do not show Expansion Indicator when there are no child items/band
In grid InitializeLayout event handler, set

UltraGrid1.DisplayLayout.Bands(0).Override.ExpansionIndicator=ShowExpansionIndicator.CheckOnDisplay
'code for increasing the default row height of the ultra grid 

UltraGrid1.DisplayLayout.Override.DefaultRowHeight = 500

'code for change column header text
In ultragrid InitializeLayout event

UltraGrid1.DisplayLayout.Bands(0).Columns(0).Header.Caption = "My header"

code for change date column format
In ultragrid InitializeLayout event

UltraGrid1.DisplayLayout.Bands(0).Columns(0).Format = "dd/mm/yyyy hh:mm:ss"


code for Adding an image to a cell
In ultragrid InitializeLayout event
now you Add an image to resource file to access from My.Resources here in the below code
UltraGrid1.DisplayLayout.Bands(0).Columns(0).CellButtonAppearance.Image = My.Resources.img

'img is the name image

'code for make Non Editable column and Editable column

'In ultragrid InitializeLayout event
'for code to allow if u want edit

UltraGrid1.DisplayLayout.Bands(0).Columns(0).CellActivation = Activation.AllowEdit

'code for locking the cell
UltraGrid1.DisplayLayout.Bands(0).Columns(0).CellActivation = Activation.NoEdit

code To add a band header
In ultragrid InitializeLayout event
'for header visibility true
UltraGrid1.DisplayLayout.Bands(0).HeaderVisible = True

' code for gave header name 
UltraGrid1.DisplayLayout.Bands(0).Header.Caption = "My Header name is write here "

'code for aligning the header text appearence 
UltraGrid1.DisplayLayout.Bands(0).Header.Appearance.TextHAlign = HAlign.right

'there are also other alignment setting in ultragrid

Xojo Real Studio

A majority of us use the web to do research – it’s faster, easier and the information is fresh.  For years I was a frequent visitor to Ramblings, a website/blog run by Aaron Ballman.  In my opinion, it was THE definitive source for many things in REALbasic.

For those of you that are new to REALbasic, Aaron was one of the REAL Software developers that worked on REALbasic.  We was with the company for seven years which is a long time in the software industry and in many respects REALbasic bears his signature.

In his new book, Ramblings on REALbasic, Aaron took many of his old blog posts, cleaned them up with new information, rearranged the order and put them in book form.  The book is divided up into Knowledge Base, REALbasic Language, User Experience, Windows, Design Patterns, Plugins, Other Languages and Just for Fun.

The Knowledge Base is a rather large collection of changes, gotchya’s, and miscellaneous information dumps about REALbasic that Aaron wrote about for years.  REALbasic is ever evolving and Aaron wrote about the bugs or misunderstandings to give us (the REALbasic developer) a little insight into what or why it happened or how we are misusing it (which happened more often than we’d like to admit).

The REALbasic Language section goes into specific REALbasic features.  I guarantee that you’ll learn something about REALbasic in this section.  Aaron writes it not as an end-user but as someone who is writing the compiler and having to support people like you and me on a regular basis.

A good portion of REALbasic developers use RB on Mac OS X and we sometimes take a Mac-centric viewpoint of developing software for Windows.  In the User Experience and Windows sections, Aaron goes into detail on some of the finer points of the Windows experience.  If you’re not a Windows expert (and even if you thought you were), these are must read sections.

The Plugins section is an alternative to REAL Softwares woefully incomplete documentation.  Aaron does a nice job of explaining how plugins work with the IDE and then goes into details that most of us will never use (unless you want to make a plugin that is).

The Design Patterns section is particularly interesting because he creates the design patterns using REALbasic.  Design patterns are coding patterns that, if you’ve been doing software long enough, you start to see over and over again.  Bigger, more complex applications probably have some of these coding patterns in them already (even if you didn’t know it) but it’s nice to get the theory and uses of them in REALbasic, up front.

Aaron does a good job of pointing out bugs and flaws in REALbasic and which versions they occurred in.  Some of those flaws are fixed in later versions of REALbasic, and he doesn’t always note if they’ve been fixed or not.  I can understand the complexity of finding out when bugs were fixed but it makes the text incomplete in my opinion.

Another missing feature, especially for the design patterns section, is downloadable project files.  It’s one thing to list the source code and explain it, but it’s entirely different to have a working example that you can step through.

While it’s sometimes nice to have a paper book to thumb through it’s getting harder and hard to justify the cost of a book that will lose its relevance in a short period of time.  This is not new to Ramblings or any book on technology but the REAL Software Rapid Release Model guarantees that any paper book will quickly become, if not obsolete, dated quickly.

Download Link : http://rapidshare.com/files/3295947299/REALbasic%202009%20Release%204.rar

Windows 8.1 Preview Now Available

Back in May, Microsoft announced the first major update to Windows 8. While the free upgrade was once codenamed Blue, a public preview of Windows 8.1 is available starting today. Most notably, Windows 8.1 brings back the Start button, a point of sincere contention for many Windows 8 users. The full release of Windows 8.1 is still scheduled for some time later this year.

Writing on the Windows Blog, Microsoft's Brandon LeBlanc runs through some of the basic improvements included in the Windows 8.1 update. The "Metro" tiles in Windows 8 are now more customizable in terms of size, allowing users to set the tiles as "really big" or "really small." LeBlanc notes this change is most applicable to tablets, where scaling down the tiles allows for more screen real estate.

"The best part is my Start screen customizations, apps, and files get synced across all my Windows 8.1 PCs and tablets, which is awesome," writes LeBlanc. "If I change my Start screen, install new apps, pin new apps to my Start screen on one PC – that all gets synced to my other PCs."

The Windows Store has also received a redesign, and beyond obligatory updates to some Windows 8 apps, Microsoft is planning to announce new applications sometime today. You can download the Windows 8.1 preview right now from the Windows Store, but as always, be sure to back up all your data before installing. As an additional note, the preview is not available for Windows RT users at this time

A Beginner’s Guide to Big O Notation

Big O notation is used in Computer Science to describe the performance or complexity of an algorithm. Big O specifically describes the worst-case scenario, and can be used to describe the execution time required or the space used (e.g. in memory or on disk) by an algorithm.

Anyone who’s read Programming Pearls or any other Computer Science books and doesn’t have a grounding in Mathematics will have hit a wall when they reached chapters that mention O(N log N) or other seemingly crazy syntax. Hopefully this article will help you gain an understanding of the basics of Big O and Logarithms.

As a programmer first and a mathematician second (or maybe third or fourth) I found the best way to understand Big O thoroughly was to produce some examples in code. So, below are some common orders of growth along with descriptions and examples where possible.

O(1)

O(1) describes an algorithm that will always execute in the same time (or space) regardless of the size of the input data set.

bool IsFirstElementNull(String[] strings)
{
 if(strings[0] == null)
 {
  return true;
 }
 return false;
}

O(N)

O(N) describes an algorithm whose performance will grow linearly and in direct proportion to the size of the input data set. The example below also demonstrates how Big O favours the worst-case performance scenario; a matching string could be found during any iteration of the for loop and the function would return early, but Big O notation will always assume the upper limit where the algorithm will perform the maximum number of iterations.

bool ContainsValue(String[] strings, String value)
{
 for(int i = 0; i < strings.Length; i++)
 {
  if(strings[i] == value)
  {
   return true;
  }
 }
 return false;
}

O(N²)

O(N²) represents an algorithm whose performance is directly proportional to the square of the size of the input data set. This is common with algorithms that involve nested iterations over the data set. Deeper nested iterations will result in O(N³), O(N⁴) etc.

bool ContainsDuplicates(String[] strings)
{
 for(int i = 0; i < strings.Length; i++)
 {
  for(int j = 0; j < strings.Length; j++)
  {
   if(i == j) // Don't compare with self
   {
    continue;
   }

   if(strings[i] == strings[j])
   {
    return true;
   }
  }
 }
 return false;
}

O(2^N)

O(2^N) denotes an algorithm whose growth will double with each additional element in the input data set. The execution time of an O(2^N) function will quickly become very large.

Logarithms

Logarithms are slightly trickier to explain so I’ll use a common example:

Binary search is a technique used to search sorted data sets. It works by selecting the middle element of the data set, essentially the median, and compares it against a target value. If the values match it will return success. If the target value is higher than the value of the probe element it will take the upper half of the data set and perform the same operation against it. Likewise, if the target value is lower than the value of the probe element it will perform the operation against the lower half. It will continue to halve the data set with each iteration until the value has been found or until it can no longer split the data set.

This type of algorithm is described as O(log N). The iterative halving of data sets described in the binary search example produces a growth curve that peaks at the beginning and slowly flattens out as the size of the data sets increase e.g. an input data set containing 10 items takes one second to complete, a data set containing 100 items takes two seconds, and a data set containing 1000 items will take three seconds. Doubling the size of the input data set has little effect on its growth as after a single iteration of the algorithm the data set will be halved and therefore on a par with an input data set half the size. This makes algorithms like binary search extremely efficient when dealing with large data sets.

This article only covers the very basics or Big O and logarithms. For a more in-depth explanation take a look at their respective Wikipedia entries: Big O Notation, Logarithms.

*Post Via "http://rob-bell.net"