By manual, it can be implemented, but limited, by choosing programmable elements, digital resistors, capacitors, inductors, including MUX, DEMUX, decoder, etc. In the case of large scale, a FPGA/CPLD will help to route connection. PSoC chops may help you some if you need a low scale

I have not seen any general analog array.

I agree with Thang Manh Hoang

Wait, the volume control and the tuning control in any ancient tube radio are already examples of "programmable analogue systems." And too, jumpers used in analogue circuit boards, to select certain functions or adjust certain features.

I think that programmability of digital vs analogue becomes ultimately a matter of degree. We used to have an analogue computer lab back in my undergrad days. They also were programmable. They consisted of banks of opamps. Programming was done by plugging individual component modules onto a board, to establish input, output, and feedback circuits for the opams, and then plugging that board onto the front of the computer. Used mainly to solve differential equations.

Somewhat like this:

https://www.youtube.com/watch?v=aLBSBqaVcxc

http://www.analogmuseum.org/english/collection/eai/tr10/

Thanks dear Mr. Singh for sending these interesting files.