The euro saw a mixed day of trading on Friday, gaining against the Japanese yen and British pound but falling versus the Canadian dollar and US dollar. The moves come a day after the European Central Bank’s monthly meeting, in which the monetary policy committee left rates unchanged at 1 percent as “excess volatility and disorderly movements in exchange rates have adverse implications for economic and financial stability.” Evidence of the impact of the euro’s appreciation came in the form of the trade surplus, which narrowed more than anticipated to 8.1 billion euros in August from a revised 14.1 billion euros, as exports fell for the first time in four months by 1.8 percent. The data adds to evidence that the outlook for the trade-dependent economy is still fragile as exchange rates and weak growth through the rest of Europe, the UK, and the US puts their own growth at risk.