Skip to content

Instantly share code, notes, and snippets.

@debjitbis08

debjitbis08/rng.js

Last active December 15, 2015 17:18
Show Gist options

  • Select an option

    Learn more about clone URLs
  • Save debjitbis08/5295038 to your computer and use it in GitHub Desktop.

Select an option

Learn more about clone URLs
Save debjitbis08/5295038 to your computer and use it in GitHub Desktop.
Download ZIP

Revisions

  1. Debjit Biswas revised this gist Apr 3, 2013. 1 changed file with 1 addition and 1 deletion.
    2 changes: 1 addition & 1 deletion rng.js
    View file
    Original file line number Diff line number Diff line change
    @@ -56,7 +56,7 @@
    };

    /* Usage */
    var a = Array(1009), i = 0, seed = 310952;
    var a = Array(1009), i = 0, seed = Date ? +new Date() : 310952;
    ranf_start(seed);
    ranf_array(a,1009);
    window.random = function () {
  2. Debjit Biswas revised this gist Apr 3, 2013. 1 changed file with 1 addition and 1 deletion.
    2 changes: 1 addition & 1 deletion rng.js
    View file
    Original file line number Diff line number Diff line change
    @@ -22,7 +22,7 @@

    var ranf_start = function (seed) {
    var t,s,j;
    var u = [];
    var u = Array(KK+KK-1);
    var ulp=(1.0/(1<<30))/(1<<22); /* 2 to the -52 */
    var ss=2.0*ulp*((seed&0x3fffffff)+2);
    var TT = 70; /* guaranteed separation between streams */
  3. Debjit Biswas revised this gist Apr 3, 2013. 1 changed file with 1 addition and 2 deletions.
    3 changes: 1 addition & 2 deletions rng.js
    View file
    Original file line number Diff line number Diff line change
    @@ -60,8 +60,7 @@
    ranf_start(seed);
    ranf_array(a,1009);
    window.random = function () {
    1009 === i && (seed = a[i-1], ranf_start(seed), ranf_array(a, 1009));
    i = 0;
    1009 === i && (seed = a[i-1], i = 0, ranf_start(seed), ranf_array(a, 1009));
    return a[i++];
    };
    })();
  4. Debjit Biswas revised this gist Apr 3, 2013. 1 changed file with 1 addition and 0 deletions.
    1 change: 1 addition & 0 deletions rng.js
    View file
    Original file line number Diff line number Diff line change
    @@ -61,6 +61,7 @@
    ranf_array(a,1009);
    window.random = function () {
    1009 === i && (seed = a[i-1], ranf_start(seed), ranf_array(a, 1009));
    i = 0;
    return a[i++];
    };
    })();
  5. Debjit Biswas revised this gist Apr 3, 2013. 1 changed file with 4 additions and 4 deletions.
    8 changes: 4 additions & 4 deletions rng.js
    View file
    Original file line number Diff line number Diff line change
    @@ -45,7 +45,7 @@
    }
    if (is_odd(s)) { /* "multiply by z" */
    for (j=KK;j>0;j--) u[j]=u[j-1];
    u[0]=u[KK]; /* shift the buffer cyclically */
    u[0]=u[KK]; /* shift the buffer cyclically */
    u[LL]=mod_sum(u[LL],u[KK]);
    }
    if (s) s>>=1; else t--;
    @@ -56,11 +56,11 @@
    };

    /* Usage */
    var a = Array(1009), i = 0;
    ranf_start(310952);
    var a = Array(1009), i = 0, seed = 310952;
    ranf_start(seed);
    ranf_array(a,1009);
    window.random = function () {
    1009 === i && (ranf_start(310952), ranf_array(a, 1009));
    1009 === i && (seed = a[i-1], ranf_start(seed), ranf_array(a, 1009));
    return a[i++];
    };
    })();
  6. Debjit Biswas revised this gist Apr 3, 2013. 1 changed file with 0 additions and 2 deletions.
    2 changes: 0 additions & 2 deletions rng.js
    View file
    Original file line number Diff line number Diff line change
    @@ -1,6 +1,4 @@
    (function () {
    "use strict";

    var KK = 100;
    var LL = 37;

  7. Debjit Biswas revised this gist Apr 3, 2013. 1 changed file with 3 additions and 4 deletions.
    7 changes: 3 additions & 4 deletions rng.js
    View file
    Original file line number Diff line number Diff line change
    @@ -1,4 +1,6 @@
    (function () {
    "use strict";

    var KK = 100;
    var LL = 37;

    @@ -60,10 +62,7 @@
    ranf_start(310952);
    ranf_array(a,1009);
    window.random = function () {
    if (i === 1009) {
    ranf_start(310952);
    ranf_array(a,1009);
    }
    1009 === i && (ranf_start(310952), ranf_array(a, 1009));
    return a[i++];
    };
    })();
  8. Debjit Biswas revised this gist Apr 3, 2013. 1 changed file with 0 additions and 2 deletions.
    2 changes: 0 additions & 2 deletions rng.js
    View file
    Original file line number Diff line number Diff line change
    @@ -1,6 +1,4 @@
    (function () {
    "use strict";

    var KK = 100;
    var LL = 37;

  9. Debjit Biswas revised this gist Apr 3, 2013. 1 changed file with 19 additions and 8 deletions.
    27 changes: 19 additions & 8 deletions rng.js
    View file
    Original file line number Diff line number Diff line change
    @@ -5,17 +5,21 @@
    var LL = 37;

    var mod_sum = function (x, y) {
    return (((x)+(y))-Math.floor(((x)+(y))))
    return x+y-(x+y|0);
    };

    var ran_u = [];
    var ran_u = Array(KK);

    var ranf_array = function (aa, n) {
    var i,j;
    for (j=0;j<KK;j++) aa[j]=ran_u[j];
    for (;j<n;j++) aa[j]=mod_sum(aa[j-KK],aa[j-LL]);
    for (i=0;i<LL;i++,j++) ran_u[i]=mod_sum(aa[j-KK],aa[j-LL]);
    for (;i<KK;i++,j++) ran_u[i]=mod_sum(aa[j-KK],ran_u[i-LL]);
    for (j=0;j<KK;j++)
    aa[j]=ran_u[j];
    for (;j<n;j++)
    aa[j] = aa[j-KK] + aa[j-LL] - (aa[j-KK] + aa[j-LL] | 0);
    for (i=0;i<LL;i++,j++)
    ran_u[i] = aa[j-KK] + aa[j-LL] - (aa[j-KK] + aa[j-LL] | 0);
    for (;i<KK;i++,j++)
    ran_u[i] = aa[j-KK] + ran_u[i-LL] - (aa[j-KK] + ran_u[i-LL] | 0);
    };

    var ranf_start = function (seed) {
    @@ -26,7 +30,7 @@
    var TT = 70; /* guaranteed separation between streams */

    function is_odd (s) {
    return ((s)&1)
    return ((s)&1);
    }

    for (j=0;j<KK;j++) {
    @@ -54,7 +58,14 @@
    };

    /* Usage */
    var a = [];
    var a = Array(1009), i = 0;
    ranf_start(310952);
    ranf_array(a,1009);
    window.random = function () {
    if (i === 1009) {
    ranf_start(310952);
    ranf_array(a,1009);
    }
    return a[i++];
    };
    })();
  10. Debjit Biswas created this gist Apr 2, 2013.
    60 changes: 60 additions & 0 deletions rng.js
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,60 @@
    (function () {
    "use strict";

    var KK = 100;
    var LL = 37;

    var mod_sum = function (x, y) {
    return (((x)+(y))-Math.floor(((x)+(y))))
    };

    var ran_u = [];

    var ranf_array = function (aa, n) {
    var i,j;
    for (j=0;j<KK;j++) aa[j]=ran_u[j];
    for (;j<n;j++) aa[j]=mod_sum(aa[j-KK],aa[j-LL]);
    for (i=0;i<LL;i++,j++) ran_u[i]=mod_sum(aa[j-KK],aa[j-LL]);
    for (;i<KK;i++,j++) ran_u[i]=mod_sum(aa[j-KK],ran_u[i-LL]);
    };

    var ranf_start = function (seed) {
    var t,s,j;
    var u = [];
    var ulp=(1.0/(1<<30))/(1<<22); /* 2 to the -52 */
    var ss=2.0*ulp*((seed&0x3fffffff)+2);
    var TT = 70; /* guaranteed separation between streams */

    function is_odd (s) {
    return ((s)&1)
    }

    for (j=0;j<KK;j++) {
    u[j]=ss; /* bootstrap the buffer */
    ss+=ss; if (ss>=1.0) ss-=1.0-2*ulp; /* cyclic shift of 51 bits */
    }
    u[1]+=ulp; /* make u[1] (and only u[1]) "odd" */
    for (s=seed&0x3fffffff,t=TT-1; t; ) {
    for (j=KK-1;j>0;j--)
    u[j+j]=u[j],u[j+j-1]=0.0; /* "square" */
    for (j=KK+KK-2;j>=KK;j--) {
    u[j-(KK-LL)]=mod_sum(u[j-(KK-LL)],u[j]);
    u[j-KK]=mod_sum(u[j-KK],u[j]);
    }
    if (is_odd(s)) { /* "multiply by z" */
    for (j=KK;j>0;j--) u[j]=u[j-1];
    u[0]=u[KK]; /* shift the buffer cyclically */
    u[LL]=mod_sum(u[LL],u[KK]);
    }
    if (s) s>>=1; else t--;
    }
    for (j=0;j<LL;j++) ran_u[j+KK-LL]=u[j];
    for (;j<KK;j++) ran_u[j-LL]=u[j];
    for (j=0;j<10;j++) ranf_array(u,KK+KK-1); /* warm things up */
    };

    /* Usage */
    var a = [];
    ranf_start(310952);
    ranf_array(a,1009);
    })();