Faster bitwise manipulation

Try this one, it uses expr and bitwise arithmetic to do the job, also simplifies message passing, so it may be a bit (!) faster.

Thanks! I *love* the elegance of this approach (and the fewer objects!), but sadly, after testing it takes roughly the same amount of time as my current approach. I think that expr is an "expensive" object, resource-wise.

Ugh, trying to replicate @KLSDIZ 's awesome expr code from the above example in Javascript was successful, but in fact performed more poorly, took almost twice the time:

inlets = 1;
outlets = 1;

var in1;
var in2;
var in3;
var in4;
var in5;
var out1;
var out2;
var out3;
var out4;

function list () {
    in1 = arguments[0];
    in2 = arguments[1];
    in3 = arguments[2];
    in4 = arguments[3];
    in5 = arguments[4];
 

    out1 = (in1 & 127) | ((in2 & 1) << 7);
    out2 = ((in2 & 126) >> 1) | ((in3 & 3) << 6);
    out3 = ((in3 & 124) >> 2) | ((in4 & 7) << 5);
    out4 = ((in4 & 120) >> 3) | ((in5 & 15) << 4);
 

    outlet (0,out1, out2, out3, out4);
}

Sorry, I take that back - I made an error in my patching, it didn't take twice as long, it took roughly the same amount of time as the other two versions...

For kicks, I tried to see if not using expr made a difference, and it did not, again roughly the same time (about 30 seconds for 20,000 iterations):

Any other ideas out there?? Feels like there's gotta be a faster way somehow!!

I think you have a bottleneck somewhere else. Using either expr or max bitwise op objects takes about 30ms on my machine (i5 from 2015), js 80ms (as expected – I believe the calculations are done efficiently because of JIT, but repackaging data between js and max takes some time). If you want to go faster, you may have to write your external (OTOH a trivial one).

We're on the same wavelength; as I was sitting in traffic this morning, thinking about the problem, I realized that I should probably look elsewhere. Most likely how I'm fetching the values (from a sysex file on disk) to send into this bit manipulation stuff. (And BTW, thanks I saw your comment about the local vars in the Javascript! :-) ).

Will mess around this weekend, hopefully I'll find a faster way than what I'm doing now. I really appreciate your help and discussion on this!

Here's my master patch where I was comparing all of the different approaches. It includes how I'm reading the sysex file from disk. The counter range represents the bytes I have to read. If you (or anyone out there) can think of a better/faster way to read the bytes out of the file, I'm all ears. Was thinking that maybe if I just read all the bytes into a coll or text object, and then worked on that? But doubt that would be faster?

oups maybe sent twice ?
bzzz

MBP 2012 i7 10.11.6 Max 8.06
seems dumping a coll faster
zzz