iamfromspacebaby

I'm putting the forumla below through a matrix and doing a cartisan to polar conversion to create a chladni pattern.

(-4755.8*pow(norm[0],7)+15454*pow(norm[0],6)-19820*pow(norm[0],5)+12702*pow(norm[0],4)-4240.1*pow(norm[0],3)+698.68*pow(norm[0],2)-49.568*norm[0]+1.4278)*cos(2*snorm[1]*PI)*cos(17.960)

However, the pattern is *perfect* and the formula is correct but there are strange artifacts in the picture attached. What are these?

I'm putting the forumla below through a matrix and doing a cartisan to polar conversion to create a chladni pattern. 

strange-artifacts-in-a-matrix

Hmm adding jit.normalize removes the artifacts... but the pattern is too blured.

That looks cool. working on cymatics stuff? if you get it working and 

dont mind, id love to look at the patch :)

Are you feeding in a float32 matrix of a char matrix? might be 

On Jul 7, 2007, at 9:57 AM, Carl Knott wrote:

> I'm putting the forumla below through a matrix and doing a cartisan 

> to polar conversion to create a chladni pattern.

> (-4755.8*pow(norm[0],7)+15454*pow(norm[0],6)-19820*pow(norm[0],5) 

> +12702*pow(norm[0],4)-4240.1*pow(norm[0],3)+698.68*pow(norm[0], 

> 2)-49.568*norm[0]+1.4278)*cos(2*snorm[1]*PI)*cos(17.960)

> However, the pattern is *perfect* and the formula is correct but 

> there are strange artifacts in the picture attached. What are these?

That looks cool. working on cymatics stuff? if you get it working and  
dont mind, id love to look at the patch :)

Are you feeding in a float32 matrix of a char matrix? might be  
rounding errors ?

> Hi,
>
> I'm putting the forumla below through a matrix and doing a cartisan  
> to polar conversion to create a chladni pattern.
>
> (-4755.8*pow(norm[0],7)+15454*pow(norm[0],6)-19820*pow(norm[0],5) 
> +12702*pow(norm[0],4)-4240.1*pow(norm[0],3)+698.68*pow(norm[0], 
> 2)-49.568*norm[0]+1.4278)*cos(2*snorm[1]*PI)*cos(17.960)
>
> However, the pattern is *perfect* and the formula is correct but  
> there are strange artifacts in the picture attached. What are these?
>
> Thanks,
>
> Carl.
>
>
>

Where are the artifacts, Carl? I'm not familiar with Chladni 

patterns and I'm curious what's wrong with your results -- they look 

Where are the artifacts, Carl?  I'm not familiar with Chladni  
patterns and I'm curious what's wrong with your results -- they look  
fine to me.

Xade - affraid thats not it, but when I get it sorted I'll give you a shout! should be a month or so.

Dan - can you see the big white blobs on the outskirts of the window.. well, they should't be there, also, sometimes I get a flashing dot in the centre of the first circle! Strange...

Any ideas? Could it be something to do with my Cart-to-polar conversion?

Xade - affraid thats not it, but when I get it sorted I'll give you a shout! should be a month or so. 

Any ideas? Could it be something to do with my Cart-to-polar conversion?


Is your data wrapping? that would be my guess. If it's oustide the

> Xade - affraid thats not it, but when I get it sorted I'll give you a shout! should be a month or so.

> Dan - can you see the big white blobs on the outskirts of the window.. well, they should't be there, also, sometimes I get a flashing dot in the centre of the first circle! Strange...

> Any ideas? Could it be something to do with my Cart-to-polar conversion?

Is your data wrapping?  that would be my guess.  If it's oustide the
range [0, 1] it won't look right.

On 7/8/07, Carl Knott  wrote:
>
> Xade - affraid thats not it, but when I get it sorted I'll give you a shout! should be a month or so.
>
> Dan - can you see the big white blobs on the outskirts of the window.. well, they should't be there, also, sometimes I get a flashing dot in the centre of the first circle! Strange...
>
> Any ideas? Could it be something to do with my Cart-to-polar conversion?
>


I'm not sure if I've wrapped it correctly Wes.

I've just written this example for you, perhaps you could take a look and try to isolate the problem for me?

I'm not sure if I've wrapped it correctly Wes. 

I've just written this example for you, perhaps you could take a look and try to isolate the problem for me? 

If you stick jit.3m at the end there, you'll see hwat the problem is.

Jit.3m reports the range of data being [-inf, inf]. Apparently you

have a singularity where the image is trashed.

> I'm not sure if I've wrapped it correctly Wes.

> I've just written this example for you, perhaps you could take a look and try to isolate the problem for me?

> #P newex 301 335 152 196617 jit.expr @expr "1 - abs(in[0])";

> #P newex 62 165 64 196617 jit.op @op +;

> #P newex 212 131 108 196617 jit.op @op * @val 0.1;

> #P newex 62 130 114 196617 jit.op @op * @val 0.94;

> #P newex 156 230 65 196617 jit.op @op *;

> #P newex 156 164 181 196617 jit.matrix 1 float32 256 256 @thru 0;

> #P newex 172 129 134 196617 jit.noise 1 float32 256 256;

> #P comment 11 46 100 196617 Virtual sand , not written by Carlos.;

> #P fasten 5 0 4 0 161 257 136 257 136 154 161 154;

If you stick jit.3m at the end there, you'll see hwat the problem is.
Jit.3m reports the range of data being [-inf, inf].  Apparently you
have a singularity where the image is trashed.

On 7/8/07, Carl Knott  wrote:
>
> I'm not sure if I've wrapped it correctly Wes.
>
> I've just written this example for you, perhaps you could take a look and try to isolate the problem for me?
>
> max v2;
> #N vpatcher 414 250 1175 936;
> #P window setfont "Sans Serif" 9.;
> #P window linecount 1;
> #P newex 408 240 48 196617 loadbang;
> #P newex 301 335 152 196617 jit.expr @expr "1 - abs(in[0])";
> #N vpatcher 464 211 1064 611;
> #P outlet 156 285 15 0;
> #P inlet 210 59 15 0;
> #P window setfont "Sans Serif" 9.;
> #P window linecount 1;
> #N vpatcher 79 161 478 415;
> #P outlet 62 194 15 0;
> #P window setfont "Sans Serif" 9.;
> #P window linecount 1;
> #P newex 62 165 64 196617 jit.op @op +;
> #P inlet 212 60 15 0;
> #P inlet 62 61 15 0;
> #P inlet 310 68 15 0;
> #P window linecount 0;
> #P newex 310 105 30 196617 !- 1.;
> #P window linecount 1;
> #P newex 212 131 108 196617 jit.op @op * @val 0.1;
> #P window linecount 0;
> #P newex 62 130 114 196617 jit.op @op * @val 0.94;
> #P connect 4 0 0 0;
> #P connect 0 0 6 0;
> #P connect 6 0 7 0;
> #P connect 1 0 6 1;
> #P fasten 3 0 0 1 315 97 171 97;
> #P connect 5 0 1 0;
> #P connect 3 0 2 0;
> #P connect 2 0 1 1;
> #P pop;
> #P newobj 156 195 45 196617 p mixer;
> #P newex 156 230 65 196617 jit.op @op *;
> #P newex 156 164 181 196617 jit.matrix 1 float32 256 256 @thru 0;
> #P newex 172 129 134 196617 jit.noise 1 float32 256 256;
> #P newex 156 91 63 196617 qmetro 100;
> #P inlet 156 59 15 0;
> #P window linecount 2;
> #P comment 11 46 100 196617 Virtual sand , not written by Carlos.;
> #P fasten 1 0 2 0 161 90;
> #P fasten 5 0 4 0 161 257 136 257 136 154 161 154;
> #P connect 2 0 4 0;
> #P connect 4 0 6 0;
> #P connect 6 0 5 0;
> #P connect 5 0 8 0;
> #P fasten 2 0 3 0 161 122 177 122;
> #P connect 3 0 6 1;
> #P connect 7 0 5 1;
> #P pop;
> #P newobj 227 381 84 196617 p setVirtualSand;
> #P newex 301 296 117 196617 jit.repos @boundmode 4;
> #N vpatcher 495 125 1095 525;
> #P outlet 132 317 15 0;
> #P window setfont "Sans Serif" 9.;
> #P window linecount 1;
> #P message 201 183 14 196617 1;
> #P newex 132 275 167 196617 jit.matrix cartopol 2 long 256 256;
> #P flonum 270 215 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
> #P flonum 201 214 35 9 0 0 0 3 0 0 0 221 221 221 222 222 222 0 0 0;
> #P newex 132 243 148 196617 jit.expr @inputs 3 @verbose 1;
> #P newex 132 152 275 196617 jit.gencoord 2 float32 256 256 @scale 2. 2. @offset -1 -1;
> #P window linecount 2;
> #P message 158 101 328 196617 expr "hypot(in[0].p[0]*in[1]\,in[0].p[1]*in[2])*dim[0]" "(((atan2(in[0].p[1]*in[2]\,in[0].p[0]*in[1])/PI)*0.5)+0.5)*dim[1]";
> #P button 132 71 15 0;
> #P inlet 132 43 15 0;
> #P comment 170 43 133 196617 Cartisian to polar conversion.;
> #P connect 1 0 2 0;
> #P connect 2 0 4 0;
> #P connect 4 0 5 0;
> #P fasten 3 0 5 0 163 138 137 138;
> #P connect 5 0 8 0;
> #P connect 8 0 10 0;
> #P fasten 2 0 3 0 137 92 163 92;
> #P fasten 2 0 9 0 137 175 206 175;
> #P connect 9 0 6 0;
> #P connect 6 0 5 1;
> #P fasten 9 0 7 0 206 206 275 206;
> #P connect 7 0 5 2;
> #P pop;
> #P newobj 408 266 77 196617 p setCartToPol;
> #P newex 227 423 205 196617 jit.window CircleMembrane @size 256 256;
> #P button 301 185 15 0;
> #P newex 301 212 142 196617 jit.matrix 1 float32 256 256;
> #P newex 301 267 45 196617 jit.expr;
> #P newex 301 27 48 196617 loadbang;
> #P newex 301 153 69 196617 prepend expr;
> #P newex 301 123 52 196617 toSymbol;
> #P window linecount 3;
> #P message 301 70 308 196617 (-697.45*pow(norm[0]\,6)+2374.6*pow(norm[0]\,5)-3165.5*pow(norm[0]\,4)+2083*pow(norm[0]\,3)-697*pow(norm[0]\,2)+107.87*norm[0]-5.5013)*cos(3*PI*snorm[1]);
> #P window linecount 2;
> #P comment 420 124 196 196617 For this one there is flickerin in the center.;
> #P comment 489 236 100 196617 U mite have to fire this urself;
> #P window linecount 6;
> #P comment 28 68 184 196617 (-788.44*pow(norm[0]\,6)+2535.6*pow(norm[0]\,5)-3137*pow(norm[0]\,4)+1866.5*pow(norm[0]\,3)-541.85*pow(norm[0]\,2)+67.561*norm[0]-2.332)* cos(1*PI*snorm[1]);
> #P comment 26 148 186 196617 (-321.41*pow(norm[0]\,6)+1243.3*pow(norm[0]\,5)-1848.9*pow(norm[0]\,4)+1322.5*pow(norm[0]\,3)-462.47*pow(norm[0]\,2)+69.878*norm[0]-2.9903)*cos(1*PI*snorm[1]);
> #P comment 27 226 183 196617 (-697.45*pow(norm[0]\,6)+2374.6*pow(norm[0]\,5)-3165.5*pow(norm[0]\,4)+2083*pow(norm[0]\,3)-697*pow(norm[0]\,2)+107.87*norm[0]-5.5013)*cos(3*PI*snorm[1]);
> #P window linecount 2;
> #P comment 36 35 100 196617 Copy and paste these examples....;
> #P window linecount 6;
> #P comment 28 306 180 196617 (173.17*pow(norm[0]\,6)-703.87*pow(norm[0]\,5)+1073.6*pow(norm[0]\,4)-769.18*pow(norm[0]\,3)+262.7*pow(norm[0]\,2)-38.31*norm[0]+1.8886)*cos(4*PI*snorm[1]);
> #P window linecount 1;
> #P comment 622 66 100 196617
> #P window linecount 3;
> #P comment 233 475 196 196617 Btw... in these examples the smallest circle where the artifact is shouldn't be there....;
> #P window linecount 1;
> #P comment 503 537 100 196617 Thank u :);
> #P fasten 13 0 20 0 306 50 232 50;
> #P connect 20 0 17 0;
> #P connect 13 0 10 0;
> #P connect 10 0 11 0;
> #P connect 11 0 12 0;
> #P fasten 12 0 16 0 306 183 306 183;
> #P connect 16 0 15 0;
> #P fasten 12 0 14 0 306 178 291 178 291 238 306 238;
> #P connect 15 0 14 0;
> #P connect 14 0 19 0;
> #P connect 19 0 21 0;
> #P connect 21 0 20 1;
> #P connect 22 0 18 0;
> #P connect 18 0 19 1;
> #P pop;
>
>


Thanks Wez, from your advice I looked at the approximation again and, though not perfect, it has something to do with my range. Thanks for ur help :)

Strange artifacts in a Matrix