Brian H.

I'm not getting what I expected from the basic [sin/cos/cycle] functions in Max.

Now let me preface this by clarifying that I'm not a total newbie in the medium and have some background in electronic music and audio recording. However, and *am* still a newbie in Max, and don't have a particularly strong math background.

OK, in the end I am trying to draw a cosine function in LCD (actually, polar plot for a bi-directional microphone) using [expr]. I wasn't getting what I expected, so started just looking at the numbers that were generated right out of the real-time audio functions. So I plugged [cycle 1] into [number~], took the float output and printed it to the Max window, and got this:

Seems like I should be getting a smoother set of values between 1 and -1, and they should be sequential. Should I expect the same numerical results from [cycle] as I would from [expr sin(angle)] with a counter banging out results?

Hopefully this makes some sense-- Can someone point me to filling in some blanks?

Thanks again-- this forum and it's contributors have been essential. One day I would like to be able to be one of them.

Hi out there,
I'm not getting what I expected from the basic [sin/cos/cycle] functions in Max.

Now let me preface this by clarifying that I'm not a total newbie in the medium and have some background in electronic music and audio recording.  However, and *am* still  a newbie in Max, and don't have a particularly strong math background.

OK, in the end I am trying to draw a cosine function in LCD (actually, polar plot for a bi-directional microphone) using [expr].  I wasn't getting what I expected, so started just looking at the numbers that were generated right out of the real-time audio functions.  So I plugged [cycle 1] into [number~], took the float output and printed it to the Max window, and got this:

expr: 0.797635
expr: 0.263692
expr: -0.311460
expr: -0.826713
expr: -0.998248
expr: -0.800536
expr: -0.268349
expr: 0.306865
expr: 0.823995
expr: 0.998515
expr: 0.803433
expr: 0.272995
expr: -0.302270
expr: -0.821238
expr: -0.992530
expr: -0.806286
expr: -0.206887
expr: 0.366444
expr: 0.818482
expr: 0.998992
expr: 0.809139
expr: 0.282275
expr: -0.428928
expr: -0.815692
expr: -0.993653
expr: -0.811967
expr: -0.286905
expr: 0.357442
expr: 0.812887
expr: 0.999383
expr: 0.721834
expr: 0.291531
expr: -0.420179
expr: -0.810076
expr: -0.994685
expr: -0.773432
expr: -0.296144
expr: 0.348409
expr: 0.807223
expr: 0.999679
expr: 0.728482
expr: 0.300757
expr: -0.476728
expr: -0.804369
expr: -0.999776
expr: -0.779514
expr: -0.305357
expr: 0.339334
expr: 0.879905
expr: 0.999865
expr: 0.735068
expr: 0.309952

Seems like I should be getting a smoother set of values between 1 and -1, and they should be sequential.  Should I expect the same numerical results from [cycle] as I would from [expr sin(angle)] with a counter banging out results?

Thanks again-- this forum and it's contributors have been essential.  One day I would like to be able to be one of them.

question-about-function-generation

well, one reason why you don;t get smoother numbers is the number~ object itself. open the nspector on it, and you probably see, that it reads out a new value only every 250 ms. this can be turned up to 10 or 20 ms, but that's the limit then.

nevertheless you can be sure, that your cycle works perfectly, the problem here is just, that you can't read it's amplitude values at signal rate.

well, one reason why you don;t get smoother numbers is the  number~ object itself. open the nspector on it, and you probably see, that it reads out a new value only every 250 ms. this can be turned up to 10 or 20 ms, but that's the limit then. 

OK, gotcha. Increased the report time. It does look a little better, but I guess I'm still not understanding why the patch below isn't drawing what I get the feeling is a fairly straightforward [expr]. I've tried troubleshooting one number at a time, and been staring too long. Anyone see anything? I'm sure it's simple:

OK, gotcha.  Increased the report time.  It does look a little better, but I guess I'm still not understanding why the patch below isn't drawing what I get the feeling is a fairly straightforward [expr].  I've tried troubleshooting one number at a time, and been staring too long.  Anyone see anything?  I'm sure it's simple:

Quote: Brian H. wrote on Wed, 10 December 2008 01:33

----------------------------------------------------

> .....I guess I'm still not understanding why the patch below isn't drawing what I get the feeling is a fairly straightforward [expr]. ....

1 - the $i2 was messing things up, I changed it to a $f2 initially and then tidied things up a bit more (patch below) but importantly changed to a float (doesn't matter that it's an int coming in, you can change type in this way using expr).

2. Importantly expr trig functions take angles in radians not degrees, so I put the conversion in for you.

Here's my version, which I think does what you want:

Quote: Brian H. wrote on Wed, 10 December 2008 01:33
----------------------------------------------------
> .....I guess I'm still not understanding why the patch below isn't drawing what I get the feeling is a fairly straightforward [expr]. ....

NICE! I knew it was something basic, either about my assumption or my execution. Floats and radians make perfect sense, and it was that easy. I had tried using floats before, didn't go back into the patch far enough for it to matter. And I knew from the output in the Max window that something in the basic numbers that were coming out of [expre] was wrong, since the pattern of what was being generated wasn't really even close. Anyway, thanks Alex & all, and now I know more about radians and to think about my floats & ints even more carefully.

NICE!  I knew it was something basic, either about my assumption or my execution.  Floats and radians make perfect sense, and it was that easy.  I had tried using floats before, didn't go back into the patch far enough for it to matter.  And I knew from the output in the Max window that something in the basic numbers that were coming out of [expre] was wrong, since the pattern of what was being generated wasn't really even close.  Anyway, thanks Alex & all, and now I know more about radians and to think about my floats & ints even more carefully.

I really dig this kind of generation via the trig functions, so here's a patch which hopefully will give some ideas. It uses [uzi] to quickly make the sine functions and puts them into buffers so they can be played back as audio. The L and R functions each have adjustable coefficients, exponents, and offsets, and adjustable rates of playback (float parameter to sig~ and then to groove~, at bottom). The middle buffer~ is the L and R either added, multiplied, or averaged.

Using basic waves like these can help sort out what's happening harmonically with the functions (or parts of them) as they're played back at different rates or combined in different ways.

I attached a screen shot as an appetizer... :)

I attached a screen shot as an appetizer...  :)

Getting back to this...I'm simply looking to generate polar graphs for common mic polar patterns using their formulas & functions. I managed to get a decent Cartesian plot of a bidirectional pattern (thanks to help from the above posts). But I'm having trouble getting anything close to a correct polar plot.

I took apart the [cartopol] help file pretty meticulously to see how it was done there, but what I'm doing is slightly different and it's not translating.

I am new at Max and a whole lot of other things coming into play here, and have been stumped and back to trial-and-error for days.

Can anyone point me back in the right direction on this?

Hi all,
Getting back to this...I'm simply looking to generate polar graphs for common mic polar patterns using their formulas & functions.  I managed to get a decent Cartesian plot of a bidirectional pattern (thanks to help from the above posts).  But I'm having trouble getting anything close to a correct polar plot.

Anyone have any offers here? I'm sure it's something quite basic. Although I know a reasonable amount about mics as an end-user, I don't know much trig! Did as much research and head-banging-on-wall as I could...

Anyone have any offers here?  I'm sure it's something quite basic.  Although I know a reasonable amount about mics as an end-user, I don't know much trig!  Did as much research and head-banging-on-wall as I could...

Question about function generation...