For starters, you won't resize the model but rather the table widget you're using to display it (see http://doc.trolltech.com/4.1/qt4-interview.html). This could either be a QTableView or QTableWidget. Get the horizontal header of the table using
Qt Code:
  1. QHeaderView* QTableView::horizontalHeader();
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And resize the section you want using
Qt Code:
  1. void QHeaderView::resizeSection(int logicalindex, int size);
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