Recipe: Bravo Find Terminals With Bands v1.2

created by SemperRabbit

Profile

• Name: Bravo Find Terminals With Bands v1.2
• ID: 109306
• Shared with: Public
• Parent: Bravo Find Terminals With Bands v1.1
• Children: None
• Created on: January 03, 2026 at 01:40 AM UTC
• Updated on: January 03, 2026 at 05:14 AM UTC

Code

-- This is an alternative method to identify terminal segments. works off the idea that you can creat a band on connected atoms.
-- correctly identifies seperate proteins, ligands, RNA, and DNA.
-- like most things in fold.it this recipe is faster with the window minimized.
-- utilizes save.Quicksave(80) for clean up.change this if save slot is need. 

-- v1.1 
    -- removed false positives cause from cuts.
    -- band search more effiecent in a single pass.
    -- removed false positives from trim.

-- v1.2 SemperRabbit 20260102
    -- removed need to delete previous bands, leveraging the return value of band.AddBetweenSegments().
    -- refactored everything into a single loop
    -- removes bands after detection and documentation
    -- removed quicksave restore at end still saves for error recovery

-- Finds terminal segments using bands between atom 3 of segment i and atom 1 of segment i+1 (adjacent segments)
-- returns Table or Terminals that is sorted with no duplicates
function findTerminalsWithBands()
    save.Quicksave(80)  -- for error recovery only, will not restore
    local segmentCount = structure.GetCount()
    -- Clear any existing bands to avoid interference

    -- check and remove false positives from trim.
    local success, err = pcall(structure.UntrimPose)
    local trim_total_segments = structure.GetCount() -- get total segments after untrim
    if trim_total_segments == segmentCount then
        --print("Pose was NOT trimmed")
    else
        print("Pose is trimmed at start of recipe")
        segmentCount = structure.GetCount()
    end

    -- identify false positives from cuts
    local table_of_cuts = structure.GetCuts()
    local k = 1
    local Terminals = {}
    -- first segment and last segment wont have bands but are always terminals
    table.insert(Terminals, 1) -- table is sorted
    
    for i = 1, segmentCount - 1 do -- minus 1 so that we don't call a non existant segment with (i+1)
        if table_of_cuts[k] == i then
            k = k + 1
            -- this is a cut, a false positive for terminals. skip it
        else
            -- Create a band between atom 3 of segment i and atom 1 of segment i+1
            local tempBand = band.AddBetweenSegments(i, i + 1, 3, 1)
            if(tempBand ~= 0) then -- successful band; found some terminals!
                -- base before end to keep Terminals table sorted
                -- don't add a duplicate
                if Terminals[#Terminals] ~= i then
                    table.insert(Terminals, i)
                end
                table.insert(Terminals, (i+1))
                band.Delete(tempBand)
            end
        end
    end
    -- first segment and last segment wont have bands but are always terminals
    -- don't add a duplicate
    if Terminals[#Terminals] ~= segmentCount then
        table.insert(Terminals, segmentCount) -- table is sorted
    end
    
    -- Print all Terminal segment indicies in one line, comma-separated
    print(" Terminals")
    print(table.concat(Terminals, ", "))
    
    -- remove bands and return user created bands
    --save.Quickload(80)
    -- return Terminals is sorted with no duplicates
    return Terminals
end


function cleanup(err)
    save.Quickload(80)
    print(" Error: " .. err)
    return {}
end

local Terminals = xpcall(findTerminalsWithBands,cleanup)

Comments

[bravosk8erboy]

table.insert is slow in fold it because of the table api overhead. use "Terminals[#Terminals + 1] =" instead.
i also figured the single quick load was faster then the multiple band deletes.