var fDesc=new Array(); fDesc[0] = "ProGriD, a desktop application that runs in Microsoft Windows, was developed to enable coordinate transformation between the official reference systems used in Brazil: Córrego Alegre, SAD69 and SIRGAS2000. It was conceived to provide geospatial data users with a tool that assists in the transition to SIRGAS2000.
ProGriD represents an advance in coordinate transformation. In general, two geodetic reference systems are related by means of transformation parameters referring to any area covered by them. What parameters cannot transform becomes residuals, which represent the distortions of the geodetic network. ProGriD models these residuals towards a more accurate final result.
ProGriD processes files containing latitude and longitude grid values that enable the direct transformation between Córrego Alegre, SAD69 and SIRGAS2000, following the NTv2 format. The choice for the NTv2 grid is due to the fact that many SIG or GPS computational programs can read this format."; function tShowHide(id, show) { var s = document.getElementById("desc"); if ((s.innerHTML.length<=212 || show==1) && show!=2) { s.innerHTML = fDesc[id]; if (document.getElementById('m1')) document.getElementById('m1').style.display='none'; if (document.getElementById('m2')) document.getElementById('m2').style.display='none'; if (document.getElementById('more_txt')) document.getElementById('more_txt').style.display='inline'; } else { s.innerHTML = ''; } }