Re: Internal algorithm how Electrum auto-selects addresses to spend money from?
Sample addresses:
11....11 0.06 BTC
22....22 0.05 BTC
33....33 0.03 BTC
44....44 0.02 BTC
55....55 0.01.BTC
BTCs to transfer: 0.09 BTC
-snip-
Which algorithm is implemented?
How about an actual test? (Amounts down by 2 decimal points 'cause I don't have enough testnet coins)11....11 0.06 BTC
22....22 0.05 BTC
33....33 0.03 BTC
44....44 0.02 BTC
55....55 0.01.BTC
BTCs to transfer: 0.09 BTC
-snip-
Which algorithm is implemented?
Done in "testnet":
Here's the coins (UTXO)
When sending 0.0009 BTC @1sat/vB, it will select "0.0006" and "0.0004" since those are the best candidates to fulfill the will-be-sent amount and the fee.
Pretty much your number 2 algorithm.
But as you can see in the replies above and the overwhelming "coinchooser.py" code of Electrum, it's much more complicated that your list.