January 3, 2007

A Nice Programming Introduction Course

Computer Science @ Princeton

Posted by sunx0170 at 1:14 PM | Resources & Links

June 18, 2006

Moto User Forum

I Love Moto

Posted by sunx0170 at 4:41 PM

May 23, 2006

Legal Problems about Condomunium Property Rights


Posted by sunx0170 at 1:05 PM

April 29, 2006

Wu Lin

Wu Lin: http://bn.sina.com.cn/xztzlm/wulinwaizhuanonline/1.shtml

Intro: http://ent.sina.com.cn/f/v/wlwz/index.shtml

Posted by sunx0170 at 2:47 PM | Resources & Links

April 17, 2006

NHGIS: National Historical Geographic Information System

National Historical Geographic Information System: NHGIS

County Data - Pre-release Versions

NHGIS County Data - Pre-release Version 1
NHGIS County Data - Pre-release Version 2
NHGIS County Data - Pre-release Version 3

Posted by sunx0170 at 5:06 PM

March 17, 2006

Improve your productivity

Home Office Productivity for Freelancers

Posted by sunx0170 at 1:48 PM

January 6, 2006

Projection and Coordinate Systems

POSC's introduction to Projection and Coordinate Systems


Posted by sunx0170 at 2:00 PM | Programming Tips

Calculating Area for Geographically Projected Data

Excerpted from ESRI's developers' Forum.

Public Function DoReturnArea(pMap As IMap, pGeomUnion As IGeometry) As Double
' Declare Variables
Dim pEnv As IEnvelope
Dim pCenterPt As IPoint
Dim pEllipticArc As IEllipticArc
Dim pNewSpatRef As ISpatialReference
Dim pSpatRefFact As ISpatialReferenceFactory

Dim pProjection As IProjection
Dim pGCS As IGeographicCoordinateSystem
Dim pUnit As IUnit
Dim pLinearUnit As ILinearUnit

' Create a projected coordinate system using the Define method.
Dim pProjCoordSysEdit As IProjectedCoordinateSystemEdit
Dim pProjCoordSys As IProjectedCoordinateSystem

' Create a SpatialReference.
Dim pSpRef1 As ISpatialReference
Dim pSpat As ISpatialReference
Dim pArea As IArea
Dim pSpatialRef As ISpatialReference

' Initalize Variables
Set pCenterPt = New Point
Set pSpatRefFact = New SpatialReferenceEnvironment

' Find the Center Point
Set pEnv = pGeomUnion.Envelope
Set pEllipticArc = CreateEArcFull(pEnv)
If Not pEllipticArc Is Nothing Then
Set pCenterPt = pEllipticArc.CenterPoint
End If

'Calculate area in acres.
'Use an Equal Area Azimuthal projection centered at the center of
'polygon feature in order to get the true area of the polygon.
Set pSpatialRef = pMap.SpatialReference
'Create a projection, gcs and unit using the factory
Set pProjection = pSpatRefFact.CreateProjection(esriSRProjection_LambertAzimuthal)
Set pGCS = pSpatRefFact.CreateGeographicCoordinateSystem(esriSRGeoCS_Clarke1866)
Set pUnit = pSpatRefFact.CreateUnit(esriSRUnit_Meter)

' The IProjectedCoordinateSystem::Define method requires a LinearUnit.
' We can simply QI for it here.
Set pLinearUnit = pUnit

' CoCreate the object.
Set pProjCoordSysEdit = New ProjectedCoordinateSystem

'Call the Define method.
pProjCoordSysEdit.Define "UserDefinedPCS", _
"UserDefinedAlias", _
"UsrDefAbbrv", _
"", _
"", _
pGCS, _
pLinearUnit, _

' QI for the PCS.
Set pProjCoordSys = pProjCoordSysEdit
If Not pCenterPt Is Nothing Then
If Not pCenterPt.IsEmpty Then
pProjCoordSys.CentralMeridian(True) = pCenterPt.x
End If
End If

Set pSpRef1 = pProjCoordSys
Set pSpat = pMap.SpatialReference

If Not pGeomUnion Is Nothing Then
Set pGeomUnion.SpatialReference = pSpatRefFact.CreateGeographicCoordinateSystem(esriSRGeoCS_AssumedGeographic1) 'pGCS 'pMxDoc.FocusMap.SpatialReference'pSpat
pGeomUnion.Project pSpRef1
Set pArea = pGeomUnion
' Convert from Square Meters to Acres by divided number with 4047.
DoReturnArea = (pArea.Area) / 4047
End If
End Function

Public Function CreateEArcFull(pEnv As IEnvelope) As IEllipticArc
On Error GoTo Handler
' If pEnv Is Nothing Then Exit Function

Dim pConstEArc As IConstructEllipticArc
Set pConstEArc = New EllipticArc
pConstEArc.ConstructEnvelope pEnv
Set CreateEArcFull = pConstEArc

'Release Objects
Set pConstEArc = Nothing
Exit Function
Set CreateEArcFull = Nothing
End Function

Sirikarn Tantipanarat
Eagle Information Mapping, Inc.
14825 St. Mary's Lane, Suite 200
Houston, Texas 77079

Posted by sunx0170 at 1:57 PM | Programming Tips

January 5, 2006

Interesting Study on "Personality"

Very interesting, though kinda intimidating


Posted by sunx0170 at 1:33 AM | What's in your mind

January 3, 2006

Graph Drawing

Infovis Infrastructures at Indiana Unversity

GraphViz - Graph Visualization Software

Posted by sunx0170 at 12:58 PM | Resources & Links