code: public void setCellMerge(final Table table, final String pos,
  							 final int rowMerge, final int columnMerge) throws FastOdsException, IOException {
  		final Position position = this.positionUtil.getPosition(pos);
  		final int row = position.getRow();
  		final int col = position.getColumn();
  		this.setCellMerge(table, row, col, rowMerge, columnMerge);
  	}
docs: Set the merging of multiple cells to one cell in all existing tables.
  
  @param table       the table where the cells to merge are
  @param pos         The cell position e.g. 'A1'
  @param rowMerge    the number of rows to merge
  @param columnMerge the number of cells to merge
  @throws FastOdsException if the row index or the col index is negative
  @throws IOException if the cells can't be merged