GAMS Data Exchange API

Writing data using integers (Mapped)
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Before writing data using a string based interface we can register strings for the unique elements, but this step is optional. The
only reason to register the strings beforehand is to enter the strings in a given order which may have advantages later in the
modelling stage.
if not gdxDataWriteStrStart(PGX,'Demand','Demand data',1,Ord(dt_par),0)
then
ReportGDXError(PGX);
IndxS[1] := 'New-York';
Values[1] := 324.0;
gdxDataWriteStr(PGX,IndxS,Values);
IndxS[1] := 'Chicago';
Values[1] := 299.0;
gdxDataWriteStr(PGX,IndxS,Values);
if not gdxDataWriteDone(PGX)
then
ReportGDXError(PGX);
In this example we write two records for a parameter that has a dimension of one.
1.1.2 Writing data using integers (Raw)
The Raw interface is suitable when we want to manage our own list of unique elements, and use an integer based index. The
Raw interface assumes that the integers assigned to the strings range from one to the number of strings registered.
Before we can write data using the Raw interface, we have to register the strings for the unique elements. The GDX routines will
assign an integer to the string that increases by one for every string registered.
if not gdxUELRegisterRawStart(PGX)
then
ReportGDXError(PGX);
gdxUELRegisterRaw(PGX,'New-York');
gdxUELRegisterRaw(PGX,'Chicago');
if not gdxUELRegisterDone(PGX)
then
ReportGDXError(PGX);
if not gdxDataWriteRawStart(PGX,'Demand','Demand data',1,Ord(dt_par),0)
then
ReportGDXError(PGX);
IndxI[1] := 1;
Values[1] := 324.0;
gdxDataWriteRaw(PGX,IndxI,Values);
IndxI[1] := 2;
Values[1] := 299.0;
gdxDataWriteRaw(PGX,IndxS,Values);
if not gdxDataWriteDone(PGX)
then
ReportGDXError(PGX);
1.1.3 Writing data using integers (Mapped)
GDX GAMS Data Exchange Writing data to
a GDX file
GAMS Data Exchange API
1.1
The Mapped interface is suitable when we want to manage our own list of unique elements, and use an integer based index. The
mapped interface lets us select our own mapping between strings for the unique elements and their integer equivalent. The
integers assigned to the unique elements should be greater equal one, and be unique for each element.
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12/3/2012