TORONTO, May 2 (Reuters) - Canada's main stock index see-sawed in early trade on Tuesday as financial stocks weighed, offsetting rises for several stocks whose earnings reports produced positive surprises, including energy company Encana Corp ECA.TO and e-commerce company Shopify SHOP.TO .
The Toronto Stock Exchange's S&P/TSX composite index .GSPTSE was up 16.1 points, or 0.1 percent, at 15,991.73 shortly after the open.