Would Samsung 950 pro ssd 512 work with my Mac Pro 2013

No, the late 2013 Mac Pro desktop is not compatible with the Samsun 850, including Pro SSD.
if you really have a 2013 MacBook Pro laptop is it early or late 2013?

Apple used a customised version of an M2 format PCI SSD drive. The Samsung 950 is an M2 format drive but is a standard M2 not the Apple custom format. As such a standard Samsung 950 will not fit. To confuse matters Samsung actually make the customised SSD drives used by Apple as well but these are only available to Apple and not as upgrades.

You can either find someone selling a genuine Apple one on say eBay and these are typically either removed from Apple Macs such as a Mac Pro, iMac, or MacBook Pro and therefore secondhand, or quite likely in some cases stolen from the factories assembling Macs for Apple.

The only other option I am aware of currently is that OWC now sell a compatible SSD drive - see http://eshop.macsales.com/shop/SSD/OWC/Aura-for-Mac-Pro/