private protected override IEnumerable <float> DoEnumerateDataValues(BufferedBinaryReader reader, DataSection dataSection, long dataPointsNumber)
{
IEnumerable <int> ReadPackedValues()
{
reader.NextUIntN();
for (var i = 0; i < dataPointsNumber; i++)
{
yield return(reader.ReadUIntN(NumberOfBits));
}
}
return(Unpack(ReadPackedValues()));
}
private protected override IEnumerable <float> DoEnumerateDataValues(BufferedBinaryReader reader, DataSection dataSection, long dataPointsNumber)
{
var mvm = MissingValueManagement;
float pmv = PrimaryMissingValue;
int ng = (int)NumberOfGroups;
int g1 = 0, gMin = 0, h1 = 0, h2 = 0, hMin = 0;
// [6-ww] 1st values of undifferenced scaled values and minimums
var os = OrderSpatial;
int ds = ExtraDescriptorsLength;
reader.NextUIntN();
int sign;
// ds is number of bytes, convert to bits -1 for sign bit
ds = ds * 8 - 1;
if (os == SpatialDifferencingOrder.FirstOrder)
{
// first order spatial differencing g1 and gMin
sign = reader.ReadUIntN(1);
g1 = reader.ReadUIntN(ds);
if (sign == 1)
{
g1 *= (-1);
}
sign = reader.ReadUIntN(1);
gMin = reader.ReadUIntN(ds);
if (sign == 1)
{
gMin *= (-1);
}
}
else if (os == SpatialDifferencingOrder.SecondOrder)
{
//second order spatial differencing h1, h2, hMin
sign = reader.ReadUIntN(1);
h1 = reader.ReadUIntN(ds);
if (sign == 1)
{
h1 *= (-1);
}
sign = reader.ReadUIntN(1);
h2 = reader.ReadUIntN(ds);
if (sign == 1)
{
h2 *= (-1);
}
sign = reader.ReadUIntN(1);
hMin = reader.ReadUIntN(ds);
if (sign == 1)
{
hMin *= (-1);
}
}
else
{
throw new BadGribFormatException("DS Error");
}
// [ww +1]-xx Get reference values for groups (X1's)
int[] x1 = new int[ng];
int nbBits = NumberOfBits;
reader.NextUIntN();
for (int i = 0; i < ng; i++)
{
x1[i] = reader.ReadUIntN(nbBits);
}
// [xx +1 ]-yy Get number of bits used to encode each group
int[] nb = new int[ng];
nbBits = BitsGroupWidths;
reader.NextUIntN();
for (int i = 0; i < ng; i++)
{
nb[i] = reader.ReadUIntN(nbBits);
}
// [yy +1 ]-zz Get the scaled group lengths using formula
// Ln = ref + Kn * len_inc, where n = 1-NG,
// ref = referenceGroupLength, and len_inc = lengthIncrement
int[] l = new int[ng];
int countL = 0;
int rgLength = (int)ReferenceGroupLength;
int lenInc = LengthIncrement;
nbBits = BitsScaledGroupLength;
reader.NextUIntN();
for (int i = 0; i < ng; i++)
{
// NG
l[i] = rgLength + reader.ReadUIntN(nbBits) * lenInc;
countL += l[i];
}
// [zz +1 ]-nn get X2 values and add X1[ i ] + X2
var data = new float[countL];
//gds.getNumberPoints() );
// used to check missing values when X2 is packed with all 1's
int[] bitsmv1 = new int[31];
//int bitsmv2[] = new int[ 31 ]; didn't code cuz number larger the # of bits
for (int i = 0; i < 31; i++)
{
bitsmv1[i] = (int)Math.Pow(2, i) - 1;
}
var count = 0;
int x2;
reader.NextUIntN();
for (int i = 0; i < ng - 1; i++)
{
for (int j = 0; j < l[i]; j++)
{
if (nb[i] == 0)
{
if (mvm == 0)
{
// X2 = 0
data[count++] = x1[i];
}
else if (mvm == ComplexPackingMissingValueManagement.Primary)
{
data[count++] = pmv;
}
}
else
{
x2 = reader.ReadUIntN(nb[i]);
if (mvm == 0)
{
data[count++] = x1[i] + x2;
}
else if (mvm == ComplexPackingMissingValueManagement.Primary)
{
// X2 is also set to missing value is all bits set to 1's
if (x2 == bitsmv1[nb[i]])
{
data[count++] = pmv;
}
else
{
data[count++] = x1[i] + x2;
}
}
}
} // end for j
} // end for i
// process last group
int last = (int)LastGroupLength;
for (int j = 0; j < last; j++)
{
// last group
if (nb[ng - 1] == 0)
{
if (mvm == 0)
{
// X2 = 0
data[count++] = x1[ng - 1];
}
else if (mvm == ComplexPackingMissingValueManagement.Primary)
{
data[count++] = pmv;
}
}
else
{
x2 = reader.ReadUIntN(nb[ng - 1]);
if (mvm == 0)
{
data[count++] = x1[ng - 1] + x2;
}
else if (mvm == ComplexPackingMissingValueManagement.Primary)
{
// X2 is also set to missing value is all bits set to 1's
if (x2 == bitsmv1[nb[ng - 1]])
{
data[count++] = pmv;
}
else
{
data[count++] = x1[ng - 1] + x2;
}
}
}
} // end for j
if (os == SpatialDifferencingOrder.FirstOrder)
{
// g1 and gMin this coding is a sort of guess, no doc
float sum = 0;
if (mvm == 0)
{
// no missing values
for (int i = 1; i < data.Length; i++)
{
data[i] += gMin; // add minimum back
}
data[0] = g1;
for (int i = 1; i < data.Length; i++)
{
sum += data[i];
data[i] = data[i - 1] + sum;
}
}
else
{
// contains missing values
float lastOne = pmv;
// add the minimum back and set g1
int idx = 0;
for (int i = 0; i < data.Length; i++)
{
if (data[i] != pmv)
{
if (idx == 0)
{
// set g1
data[i] = g1;
lastOne = data[i];
idx = i + 1;
}
else
{
data[i] += gMin;
}
}
}
if (lastOne == pmv)
{
throw new BadGribFormatException("DS bad spatial differencing data");
}
for (int i = idx; i < data.Length; i++)
{
if (data[i] != pmv)
{
sum += data[i];
data[i] = lastOne + sum;
lastOne = data[i];
}
}
}
}
else if (os == SpatialDifferencingOrder.SecondOrder)
{
//h1, h2, hMin
float hDiff = h2 - h1;
float sum = 0;
if (mvm == 0)
{
// no missing values
for (int i = 2; i < data.Length; i++)
{
data[i] += hMin; // add minimum back
}
data[0] = h1;
data[1] = h2;
sum = hDiff;
for (int i = 2; i < data.Length; i++)
{
sum += data[i];
data[i] = data[i - 1] + sum;
}
}
else
{
// contains missing values
int idx = 0;
float lastOne = pmv;
// add the minimum back and set h1 and h2
for (int i = 0; i < data.Length; i++)
{
if (data[i] != pmv)
{
if (idx == 0)
{
// set h1
data[i] = h1;
sum = 0;
lastOne = data[i];
idx++;
}
else if (idx == 1)
{
// set h2
data[i] = h1 + hDiff;
sum = hDiff;
lastOne = data[i];
idx = i + 1;
}
else
{
data[i] += hMin;
}
}
}
if (lastOne == pmv)
{
throw new BadGribFormatException("DS bad spatial differencing data");
}
for (int i = idx; i < data.Length; i++)
{
if (data[i] != pmv)
{
sum += data[i];
data[i] = lastOne + sum;
lastOne = data[i];
}
}
}
} // end h1, h2, hMin
// formula used to create values, Y * 10**D = R + (X1 + X2) * 2**E
var d = DecimalScaleFactor;
var dd = Math.Pow(10, d);
var r = ReferenceValue;
var e = BinaryScaleFactor;
var ee = Math.Pow(2.0, e);
if (mvm == 0)
{
// no missing values
for (int i = 0; i < data.Length; i++)
{
data[i] = (float)((r + data[i] * ee) / dd);
}
}
else
{
// missing value == 1
for (int i = 0; i < data.Length; i++)
{
if (data[i] != pmv)
{
data[i] = (float)((r + data[i] * ee) / dd);
}
}
}
return(data);
}
private protected override IEnumerable <float> DoEnumerateDataValues(BufferedBinaryReader reader, DataSection dataSection, long dataPointsNumber)
{
var mvm = MissingValueManagement;
var pmv = PrimaryMissingValue;
var ng = (int)NumberOfGroups;
// 6-xx Get reference values for groups (X1's)
var x1 = new int[ng];
var nbBits = NumberOfBits;
for (var i = 0; i < ng; i++)
{
x1[i] = reader.ReadUIntN(nbBits);
}
// [xx + 1 ]-yy Get number of bits used to encode each group
var nb = new int[ng];
nbBits = BitsGroupWidths;
reader.NextUIntN();
for (var i = 0; i < ng; i++)
{
nb[i] = reader.ReadUIntN(nbBits);
}
// [yy +1 ]-zz Get the scaled group lengths using formula
// Ln = ref + Kn * len_inc, where n = 1-NG,
// ref = referenceGroupLength, and len_inc = lengthIncrement
var l = new int[ng];
var rgLength = (int)ReferenceGroupLength;
var lenInc = LengthIncrement;
nbBits = BitsScaledGroupLength;
reader.NextUIntN();
for (var i = 0; i < ng; i++)
{
// NG
l[i] = rgLength + reader.ReadUIntN(nbBits) * lenInc;
}
// [zz +1 ]-nn get X2 values and calculate the results Y using formula
// Y * 10**D = R + (X1 + X2) * 2**E
var d = DecimalScaleFactor;
var dd = Math.Pow(10, d);
var r = ReferenceValue;
var e = BinaryScaleFactor;
var ee = Math.Pow(2.0, e);
// used to check missing values when X2 is packed with all 1's
var bitsmv1 = new int[31];
for (var i = 0; i < 31; i++)
{
bitsmv1[i] = (int)Math.Pow(2, i) - 1;
}
int x2;
reader.NextUIntN();
for (var i = 0; i < ng - 1; i++)
{
for (var j = 0; j < l[i]; j++)
{
if (nb[i] == 0)
{
if (mvm == 0)
{
// X2 = 0
yield return((float)((r + x1[i] * ee) / dd));
}
else if (mvm == ComplexPackingMissingValueManagement.Primary)
{
yield return(pmv);
}
}
else
{
x2 = reader.ReadUIntN(nb[i]);
if (mvm == 0)
{
yield return((float)((r + (x1[i] + x2) * ee) / dd));
}
else if (mvm == ComplexPackingMissingValueManagement.Primary)
{
// X2 is also set to missing value is all bits set to 1's
if (x2 == bitsmv1[nb[i]])
{
yield return(pmv);
}
else
{
yield return((float)((r + (x1[i] + x2) * ee) / dd));
}
}
}
} // end for j
} // end for i
// process last group
var last = (int)LastGroupLength;
for (var j = 0; j < last; j++)
{
// last group
if (nb[ng - 1] == 0)
{
if (mvm == 0)
{
// X2 = 0
yield return((float)((r + x1[ng - 1] * ee) / dd));
}
else if (mvm == ComplexPackingMissingValueManagement.Primary)
{
yield return(pmv);
}
}
else
{
x2 = reader.ReadUIntN(nb[ng - 1]);
if (mvm == 0)
{
yield return((float)((r + (x1[ng - 1] + x2) * ee) / dd));
}
else if (mvm == ComplexPackingMissingValueManagement.Primary)
{
// X2 is also set to missing value is all bits set to 1's
if (x2 == bitsmv1[nb[ng - 1]])
{
yield return(pmv);
}
else
{
yield return((float)((r + (x1[ng - 1] + x2) * ee) / dd));
}
}
}
} // end for j
}
