Prototype and description of the function getntvminmaxshift() (Function of the unlock requiring group "NTv2 Tools") |
getntvminmaxshift() Determination of the min / max shift values of one or all NTv2 grids. Prototype of the DLL function in C++ syntax (attend lower case!): extern "C" __declspec(dllimport) unsigned long __stdcall getntvminmaxshift( const char *pszFileNtv, unsigned long lAscii, unsigned short nGridNo, double *fMinShift, double *fMaxShift) Prototype of the DLL function in Visual Objects syntax: _DLL function getntvminmaxshift; (pszFileNtv as psz,; // 4 Byte, char* lAscii as logic,; // 4 Byte nGridNo as word,; // 2 Byte fMinShift ref real8,; // 4 Byte fMaxShift ref real8); // 4 Byte as logic pascal:geodll32.getntvminmaxshift The parameters are passed and/or returned as follows: pszFileNtv File name of the ASCII or binary formatted NTv2 file from which the minimum and maximum shift values are to be determined. The file name may contain a drive letter, a directory path and a file name extension. lAscii TRUE: The NTv2 file is ASCII formatted. FALSE: The NTv2 file is binary formatted. nGridNo n: Number of the grid from which the the minimum and maximum shift values are to be determined. 0: The minimum and maximum shift values of all grids contained in the NTv2 file are added together. fMinShift Smallest (minimum) shift value of one or all NTv2 grids. (ref) The value is the absolute value of the smallest determined shift value in geodetic seconds, which is calculated from the shifts in latitude and longitude according to Pytagoras. fMaxShift Largest (maximum) shift value of one or all NTv2 grids. (ref) The value is the absolute value of the largest determined shift value in geodetic seconds, which is calculated from the shifts in latitude and longitude according to Pytagoras. returnVal In case of an error the function returns FALSE, otherwise TRUE. Unlocking: This function is a component of the unlock requiring function group "NTv2 tools". It is unlocked for unrestricted use together with the other functions of the group by passing the unlock parameters, acquired from the software distribution company, trough the function setunlockcode(). Without unlocking no calls for test purposes (shareware principle) are possible with this function. |