What is the diameter of the pipe and how far is it from the wall? A toilet needs a 3 or 4" drain line and it does not have a trap (it's part of the toilet, as opposed to a shower drain or a tub drain which needs to be below it). Does this pipe have a cap on it? If so, take it off, look to see if there is any standing water (probably not). Pour some water down the pipe. Does it drain? Is there any standing water there now? Is there a vent line near the pipe coming out of the floor? If it has a screw off plug, it is most likely NOT a drain line for a toilet.v My unprofessional opinion.