Plot Total Alkali Silica (TAS) chart

plotTAS will plot magma compositions on a standard TAS chart with type delineations and labels.

plotTAS will identify and plot a magma based on composition of oxides.
- Input any number of vectors containing magma compositions.
- Composition vectors must contain normalized weight percentages of
oxides, in the following order:
SiO2, TiO2, Al2O3, FeO, MnO, MgO, CaO, Na2O, K2O, P2O5

- Alternately, the input can be a matrix containing multiple samples. Each column will be read as a separate sample. If your matrix of samples has each sample on its own row, simply transpose the matrix when calling the function.

- The input magmas will be plotted on a magma composition chart using standard values for magma composition.

If the points should be labeled, include a cell array with the labels as
the last argument of the function.

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EXAMPLES:

magma1 = [72.59, 0.258, 14.77, 1.95, 0.053, 0.89, 2.25, 3.63, 3.54, 0.067];
magma2 = [77.02, 0.151, 12.56, 0.71, 0.006, 0.01, 0.15, 3.15, 6.20, 0.033];
plotTAS(magma1, magma2)

magma3 = [65.32, 0.948, 14.30, 7.29, 0.236, 0.89, 3.36, 3.89, 3.32, 0.457];
names = {'magma1', 'magma2', 'magma3'};
plotTAS(magma1, magma2, names);

matrixSamples = [magma1', magma2', magma3'];

plotTAS(matrixSamples);
plotTAS(matrixSamples, names);