Oceangirl10, that question is not really answerable without more information, particularly about the dirve type on the mac, and the amount of effort and resource the person trying to recover the data has.
The short answer is if a secure delete with at least a couple of writes is done on a HD drive, and the data is not cached elsewhere then for a layperson it would not be recoverable.
The iPhone is more complicated and depends on how full the phone is amount of data written since they were deleted. I haven't done so for years, but you used to be able to go into dfu mode and use specific software you could recover some data.
As somebody with some experience in data recovery, I can tell you it's not possible after SECURE empty trash. Are you sure you actually did SECURE empty trash? I think this option has been removed in Yosemite.
Secure empty trash overwrites data blocks on mass storage device. Software recovery is not possible after such procedure. Hardware recovery might be possible, but it will be pricey and not guaranteed to work.
If it wasn't secure empty trash but regular empty trash, the probability of successful recovery depends on the amount of data written since then and amount of free space. You should refrain from using your notebook, get proper software (like Data Rescue) and scan drive for these files ASAP. Start with Deep Scan, as quick scan is not so quick and very unlikely to do the job.
As to the iPhone, I have never been successful doing that. Attempt would be possible if you could mount iOS device's storage as a regular hard drive. I presume such procedure would be possible after jailbraking. Even then, iPhone's mass storage is encrypted and anybody attempting data extraction would nearly certainly be unsuccessful.
If you had copies of this file but only SECURE empty trashed a few of the copies, recovery will be possible.
If you do Time Machine backups, your files might still be found there even despite deleting them. Please check your Time Machine to find out if files can be found there.
I agree that consumer level software recovery is unlikely to yield anything. If these files are of extremely high importance, I would stop using the device(s) immediately and call a competent professional data recovery firm. However, going into it, I would also be prepared for a price tag that can quickly get into the four figure territory.