Stocks edge up after 3 days of losses

NEW YORK (AP) — Energy and materials companies are pushing stocks higher as prices for oil and other commodities rose, but mixed earnings reports from retailers are tempering gains.

Oil rose to nearly $100 a barrel because of a weaker dollar, sending energy stocks in the S&P 500 up the most of the 10 industry groups in the index.

The Dow Jones industrial average is up 20 points, or 0.2 percent, at 12,500. The Standard & Poor’s 500 index is up 6 points, or 0.4 percent, at 1,334.

Strong earnings from Dell Inc. helped push the technology-focused Nasdaq composite index up 14 points, or 0.5 percent, at 2,797.

Staples Inc. plunged 19 percent after the office-supply company reported sales that were weaker than investors were expecting. The company also lowered its full-year earnings forecast.