To use own data set, this should be a plain ASCII file with samples
organsised as rows and grain-size classes organised as columns. The ASCII
file can be separated by spaces, commas, semi colons or tab stops. The
file may contain a leading column with sample IDs and/or one leading row
with grain-size class breaks. To run EMMA make sure that there are no
classes that contain only zeros throught all samples (i.e., remove them
beforehand, e.g., by X = X[,colSums(X) > 0]
).