code: public void setCellMergeInAllTables(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.setCellMergeInAllTables(row, col, rowMerge, columnMerge);
  	}
docs: Set the merging of multiple cells to one cell in all existing tables.
  
  @param pos
  The cell position e.g. 'A1'
  @param rowMerge the number of rows to merge
  @param columnMerge the number of columns to merge
  @throws FastOdsException if the row index or the col index is negative
  @throws IOException if the cells can't be merged