rewrite TRNOISE, with the intention to separate the noise sequenze computation

from its use in the VSRC device.

ChangeLog

@@ -1,7 +1,19 @@
+2010-12-12  Robert Larice
+ * src/frontend/miscvars.c ,
+ * src/frontend/trannoise/1-f-code.c ,
+ * src/include/1-f-code.h ,
+ * src/include/fftext.h ,
+ * src/spicelib/devices/vsrc/vsrcacct.c ,
+ * src/spicelib/devices/vsrc/vsrcdefs.h ,
+ * src/spicelib/devices/vsrc/vsrcload.c ,
+ * src/spicelib/devices/vsrc/vsrcpar.c :
+    rewrite TRNOISE, with the intention to separate the noise sequenze computation
+      from its use in the VSRC device.
+
 2010-12-12 Holger Vogt
  * vsrcacct.c: Patch von R. Larice für sichere Breakpoints
    bei TRNOISE
-   
+
 2010-12-11  Robert Larice
  * src/include/bool.h :
     Change bool from `unsigned char' to `int'

src/frontend/miscvars.c

@@ -94,6 +94,7 @@ char *ft_setkwords[] = {
     "noprintscale",
     "nosort",
     "nosubckt",
+    "notrnoise",
     "numdgt",
     "opts",
     "pivrel",

src/frontend/trannoise/1-f-code.c

@@ -12,8 +12,10 @@
 #include <stddef.h>
 #include <stdlib.h>
 #include <stdarg.h>			// var. argumente
-#include "1-f-code.h"
 #include "ngspice.h"
+#include "cpextern.h"
+#include "cktdefs.h"
+#include "1-f-code.h"
 
 #include "fftext.h"
 #include "wallace.h"
@@ -60,3 +62,104 @@ float alpha)
    fprintf(stdout,"%d (2e%d) one over f values created\n", n_pts, n_exp);
 }
 
+
+
+/*-----------------------------------------------------------------------------*/
+
+void
+trnoise_state_gen(struct trnoise_state *this, CKTcircuit *ckt)
+{
+    if(this->top == 0) {
+
+        if(cp_getvar("notrnoise", CP_BOOL, NULL))
+            this -> NA = this -> TS = this -> NALPHA = this -> NAMP = 0.0;
+
+        if((this->NALPHA > 0.0) && (this->NAMP > 0.0)) {
+
+            // add 10 steps for start up sequence
+            size_t nosteps = (size_t) (ckt->CKTfinalTime / this->TS) + 10;
+
+            size_t newsteps = 1;
+            long int newexp = 0;
+            // generate number of steps as power of 2
+            while(newsteps < nosteps) {
+                newsteps <<= 1;
+                newexp++;
+            }
+
+            this->oneof = TMALLOC(float, newsteps);
+            this->oneof_length = newsteps;
+
+            f_alpha((int) newsteps, newexp,
+                    this -> oneof,
+                    (float) this -> NAMP,
+                    (float) this -> NALPHA);
+        }
+
+        trnoise_state_push(this, 0.0); /* first is deterministic */
+        return;
+    }
+
+
+    // make use of two random variables per call to rgauss()
+    {
+        double ra1, ra2;
+        double NA = this -> NA;
+
+        if(NA != 0.0) {
+
+#ifdef FastRand
+            // use FastNorm3
+            ra1 = NA * FastNorm;
+            ra2 = NA * FastNorm;
+#elif defined (WaGauss)
+            // use WallaceHV
+            ra1 = NA * GaussWa;
+            ra2 = NA * GaussWa;
+#else
+            rgauss(&ra1, &ra2);
+            ra1 *= NA;
+            ra2 *= NA;
+#endif
+
+        } else {
+
+            ra1 = 0.0;
+            ra2 = 0.0;
+
+        }
+
+        if(this -> oneof) {
+
+            if(this->top + 1 >= this->oneof_length) {
+                fprintf(stderr,"ouch, noise data exhausted\n");
+                exit(1);
+            }
+
+            ra1 += this->oneof[this->top]      -  this->oneof[0];
+            ra2 += this->oneof[this->top + 1]  -  this->oneof[0];
+        }
+
+        trnoise_state_push(this, ra1);
+        trnoise_state_push(this, ra2);
+    }
+
+}
+
+
+struct trnoise_state *
+trnoise_state_init(double NA, double TS, double NALPHA, double NAMP)
+{
+    struct trnoise_state *this = TMALLOC(struct trnoise_state, 1);
+
+    this->NA = NA;
+    this->TS = TS;
+    this->NALPHA = NALPHA;
+    this->NAMP = NAMP;
+
+    this -> top = 0;
+
+    this -> oneof = NULL;
+
+    return this;
+}

src/include/1-f-code.h

@@ -5,3 +5,45 @@ void f_alpha(int n_pts, int n_exp, float X[], float Q_d,
 float alpha);
 
 void rvfft(float X[], unsigned long int n);
+
+
+#define TRNOISE_STATE_MEM_LEN 4
+struct trnoise_state
+{
+    double points[TRNOISE_STATE_MEM_LEN];
+    size_t top;
+
+    double NA, TS, NAMP, NALPHA;
+
+    float *oneof;
+    size_t oneof_length;
+};
+
+
+struct trnoise_state *trnoise_state_init(double NA, double TS, double NALPHA, double NAMP);
+
+void trnoise_state_gen(struct trnoise_state *this, CKTcircuit *ckt);
+void trnoise_state_free(struct trnoise_state *this);
+
+
+static inline void
+trnoise_state_push(struct trnoise_state *this, double val)
+{
+    this->points[this->top++ % TRNOISE_STATE_MEM_LEN] = val;
+}
+
+
+static inline double
+trnoise_state_get(struct trnoise_state *this, CKTcircuit *ckt, size_t index)
+{
+    while(index >= this->top)
+        trnoise_state_gen(this, ckt);
+
+    if(index + TRNOISE_STATE_MEM_LEN < this->top) {
+        fprintf(stderr, "ouch, trying to fetch from the past %d %d\n",
+                index, this->top);
+        exit(1);
+    }
+
+    return this->points[index % TRNOISE_STATE_MEM_LEN];
+}

src/include/fftext.h

@@ -16,7 +16,7 @@ int fftInit(long M);
 /* OUTPUTS */
 /* private cosine and bit reversed tables	*/
 
-void fftFree();
+void fftFree(void);
 // release storage for all private cosine and bit reversed tables
 
 void ffts(float *data, long M, long Rows);

src/spicelib/devices/vsrc/vsrcacct.c

@@ -10,6 +10,7 @@ Author: 1985 Thomas L. Quarles
 #include "sperror.h"
 #include "suffix.h"
 #include "missing_math.h"
+#include "1-f-code.h"
 
 extern int fftInit(long M);
 extern void fftFree(void);
@@ -193,21 +194,18 @@ VNoi1 1 0  DC 0 TRNOISE(0n 0.5n 1 10n) : generate 1/f noise
                         0,  time step, exponent < 2, rms value
 */
                 case TRNOISE: {
-                    double NA, NT, NALPHA, NAMP, TS;
 
-                    NA = here->VSRCcoeffs[0]; // input is rms value
-                    NT = here->VSRCcoeffs[1]; // time step
+                    struct trnoise_state *state = here -> VSRCtrnoise_state;
+                    double TS = state -> TS;
 
-                    NALPHA = here->VSRCfunctionOrder > 2
-                       ? here->VSRCcoeffs[2] : 0.0;
-                    NAMP = here->VSRCfunctionOrder > 3
-                       && here->VSRCcoeffs[3] != 0.0
-                       && here->VSRCcoeffs[2] != 0.0       
-                       ? here->VSRCcoeffs[3] : 0.0;
-
-                    if ((NT == 0.) || ((NA == 0.) && (NAMP == 0.))) // no further breakpoint if value not given
+                    if (TS == 0.0) // no further breakpoint if value not given
                         break;
-                    TS = NT;
+
+                    /* FIXME, dont' want this here, over to aof_get or somesuch */
+                    if (ckt->CKTtime == 0.0) {
+                        printf("VSRC: free fft tables\n");
+                        fftFree();
+                    }
 
                     if(ckt->CKTbreak) {
 

src/spicelib/devices/vsrc/vsrcdefs.h

@@ -11,6 +11,8 @@ Author: 1985 Thomas L. Quarles
 #include "gendefs.h"
 #include "complex.h"
 
+struct trnoise_state;
+
         /*
          * structures to describe independent voltage sources
          */
@@ -49,14 +51,7 @@ typedef struct sVSRCinstance {
     double VSRCdF1phase; /* distortion f1 phase */
     double VSRCdF2phase; /* distortion f2 phase */
     
-    /*transient noise*/
-    double VSRCprevTime; /*last time a new random value was issued*/
-    double VSRCprevVal;  /*last value issued at prevTime*/
-    double VSRCnewVal;   /*new value issued at prevTime*/    
-    double VSRCsecRand;  /*second random value not yet used*/
-    float *VSRConeof;    /*pointer to array of 1 over f noise values */
-    long int VSRCncount; /* counter to retrieve noise values */
-    /*end of noise*/
+    struct trnoise_state *VSRCtrnoise_state; /* transient noise */
 	
     double VSRCr;           /* pwl repeat */
     double VSRCrdelay;     /* pwl delay period */

src/spicelib/devices/vsrc/vsrcload.c

@@ -11,14 +11,6 @@ $Id$
 #include "trandefs.h"
 #include "sperror.h"
 #include "suffix.h"
-#undef WaGauss
-#ifdef FastRand
-#include "FastNorm3.h"
-#elif defined (WaGauss)
-#include "wallace.h"
-#else
-extern void rgauss(double* py1, double* py2);
-#endif
 #include "1-f-code.h"
 
 #ifdef XSPICE_EXP
@@ -343,204 +335,24 @@ VNoi1 1 0  DC 0 TRNOISE(0n 0.5n 1 10n) : generate 1/f noise
                         0,  time step, exponent < 2, rms value
 */
                 case TRNOISE: {
-                /* Generate voltage point every TS with amplitude NA * ra,
-                   where ra is drawn from a random number generator with
-                   gaussian distribution with mean 0 and standard deviation 1 
-				*/
 
-//#define PRVAL
-//                    typedef int bool;
-   
-                    double newval=0.0, lastval=0.0, lasttime=0.0;
-                    double NA, NT, TS;                    
-                    double V1, V2, basetime = 0.;
-                    double scalef, ra1, ra2;
-                    float NALPHA, NAMP;
-   
-                    long int nosteps, newsteps = 1, newexp = 0;
-             
-                    bool aof = FALSE;   
-                       
-                    NA = here->VSRCcoeffs[0]; // input is rms value
-                    NT = here->VSRCcoeffs[1]; // time step
+                    struct trnoise_state *state = here -> VSRCtrnoise_state;
 
-                    scalef = NA;
-//                    scalef = NA*1.32;
+                    double TS = state -> TS;
 
-                    NALPHA = here->VSRCfunctionOrder > 2
-                       ? (float)here->VSRCcoeffs[2] : 0.0f;
-                    NAMP = here->VSRCfunctionOrder > 3
-                       && here->VSRCcoeffs[3] != 0.0
-                       && here->VSRCcoeffs[2] != 0.0       
-                       ? (float)here->VSRCcoeffs[3] : 0.0f;
+                    if(TS == 0.0) {
+                        value = 0.0;
+                    } else {
+                        size_t n1 = (size_t) floor(time / TS);
 
-                    if ((NT == 0.) || ((NA == 0.) && (NAMP == 0.))) {
-                        value =  here->VSRCdcValue;
-                        goto noiDone;
-                    }
-                    else
-                        TS = NT; /* time step for noise */
-        
-                    if ((NALPHA > 0.0) && (NAMP > 0.0)) aof = TRUE;
-   
-                    lasttime = here->VSRCprevTime;
-                    lastval = here->VSRCprevVal;
-                    newval = here->VSRCnewVal;
-                    /* set all data: DC, white, 1of */
-                    if (time <= 0 /*ckt->CKTstep*/) {
-                        /* data are already set */
-                        if ((here->VSRCprevVal != 0) || (here->VSRCnewVal != 0)) {
-                            value = here->VSRCprevVal;
-                            goto noiDone;
-                        }
-                        lasttime = 0.0;
-                        here->VSRCsecRand = 2.; /* > 1, invalid number out of the random number range */
-                        /* get two random samples */
-#ifdef FastRand
-                        // use FastNorm3
-                        here->VSRCprevVal = scalef * GaussWa;
-                        here->VSRCnewVal = scalef * GaussWa; 
-#elif defined (WaGauss)
-                        // use WallaceHV
-                        here->VSRCprevVal = scalef * GaussWa;
-                        here->VSRCnewVal = scalef * GaussWa;
-#else
-                        // make use of two random variables per call to rgauss()
-                        rgauss(&ra1, &ra2);
-                        here->VSRCprevVal = scalef * ra1;
-                        // choose to set start value to 0
-                        here->VSRCprevVal = 0;
-                        here->VSRCnewVal = scalef * ra2;
-#endif
-                        /* generate 1 over f noise at time 0 */
-                        if (aof) {
-                            if (here->VSRCncount==0) {
-                                // add 10 steps for start up sequence
-                                nosteps = (long)((ckt->CKTfinalTime)/TS) + 10;
-                                // generate number of steps as power of 2
-                                while(newsteps < nosteps) {
-                                    newsteps <<= 1;
-                                    newexp++;
-                                }
-                                here->VSRConeof = TMALLOC(float, newsteps); //(float *)tmalloc(sizeof(float) * newsteps);
-#ifdef PRVAL
-                                printf("ALPHA: %f, GAIN: %e\n", NALPHA, NAMP);
-#endif
-                                f_alpha(newsteps, newexp, here->VSRConeof, NAMP, NALPHA);
-#ifdef PRVAL
-                                printf("Noi1: %e, Noi2: %e\n", here->VSRConeof[10], here->VSRConeof[100]);                            
-#endif
-                                here->VSRCprevVal += here->VSRConeof[here->VSRCncount];                         
-                                here->VSRCncount++;
-                                here->VSRCnewVal += here->VSRConeof[here->VSRCncount];
-                                here->VSRCncount++;
-                                value = newval;
-                                // add DC
-                                here->VSRCprevVal += here->VSRCdcValue;
-                                here->VSRCnewVal += here->VSRCdcValue;
-                                value = here->VSRCprevVal;
-#ifdef PRVAL
-                                printf("start1, time: %e, outp: %e, rnd: %e\n", time, newval, testval);
-#endif
-                            } else { // here->VSRCncount > 0
-                                // add DC
-                                here->VSRCprevVal += here->VSRCdcValue;
-                                here->VSRCnewVal += here->VSRCdcValue;
-                                value = here->VSRCprevVal;
-#ifdef PRVAL
-						        printf("start2, time: %e, outp: %e, rnd: %e\n", time, here->VSRCprevVal, testval);
-#endif                        
-                            }         
-#ifdef PRVAL
-                            printf("time 0 value: %e for %s\n", here->VSRCprevVal, here->VSRCname);
-#endif   
-                            goto loadDone;                         
-                        }  //aof
-                        // add DC
-                        here->VSRCprevVal += here->VSRCdcValue;
-                        here->VSRCnewVal += here->VSRCdcValue;
-                        value = here->VSRCprevVal;
-                        here->VSRCprevTime = 0.;
-                        goto loadDone;
-                    }  // time < 0                   
+                        double V1 = trnoise_state_get(state, ckt, n1);
+                        double V2 = trnoise_state_get(state, ckt, n1+1);
 
-                    V1 = here->VSRCprevVal;
-                    V2 = here->VSRCnewVal;
-                    if (here->VSRCprevTime == ckt->CKTtime) {
-                        value = here->VSRCprevVal;
-                        goto noiDone;
+                        value = V1 + (V2 - V1) * (time / TS - n1);
                     }
 
-                    if (time > 0 && time < TS) {
-                        value = V1 + (V2 - V1) * (time) / TS;
-                    }
-                    else if (time >= TS) {
-                     /* repeating signal - figure out where we are in period */
-                     /* numerical correction to avoid basetime less than 
-                     next step, e.g. 4.99999999999999995 delivers a floor
-                     of 4 instead of 5 */
-                        basetime = TS * floor(time*1.000000000001/TS);
-                        time -= basetime;
-
-#define NSAMETIME(a,b) (fabs((a)-(b))<= NTIMETOL * TS)
-#define NTIMETOL 1e-7
-
-                        if NSAMETIME(time,0.) {
-
-                        /* get new random number */
-#ifdef FastRand
-                            // use FastNorm3
-                            newval = scalef * FastNorm;
-#elif defined (WaGauss)
-                            // use WallaceHV
-                            newval = scalef * GaussWa;
-#else
-                            // make use of two random variables per call to rgauss()
-                            if (here->VSRCsecRand == 2.0) {  
-                                rgauss(&ra1, &ra2);
-                                newval = scalef * ra1;
-                                here->VSRCsecRand = scalef * ra2;
-                            }
-                            else {
-                                newval = here->VSRCsecRand;
-                                here->VSRCsecRand = 2.0;
-                            }
-#endif
-                            V1 = here->VSRCprevVal = here->VSRCnewVal;
-                            V2 = newval; // scale factor t.b.d.
-                            if(here->VSRCdcGiven) V2 += here->VSRCdcValue;
-                            if (aof) {                        
-                                V2 += here->VSRConeof[here->VSRCncount];
-#ifdef PRVAL
-                                printf("aof: %d\n", here->VSRCncount);
-#endif
-                            }
-                            here->VSRCncount++;
-                            value = V1;
-                            here->VSRCnewVal = V2;
-                        } else if (time > 0 && time < TS) {
-                            value = V1 + (V2 - V1) * (time) / TS;
-#ifdef PRVAL
-                            printf("if1, time: %e, outp: %e, rnd: %e\n", ckt->CKTtime, 
-						        V1 + (V2 - V1) * (time) / TS, V2);
-#endif
-                        } else { /* time > TS should be never reached */
-                            value = V1 + (V2 - V1) * (time-TS) / TS;
-#ifdef PRVAL
-                            printf("if2, time: %e, outp: %e, rnd: %e\n", ckt->CKTtime, 
-						        V1 + (V2 - V1) * (time-TS) / TS, V2);
-#endif                  
-                        }
-                        here->VSRCprevTime = ckt->CKTtime;
-                    }
-noiDone:                   
-                    if (time >=ckt->CKTfinalTime) {
-                        /* free the 1of memory */
-                        if (here->VSRConeof) tfree(here->VSRConeof);
-                        /* reset the 1of counter */
-                        here->VSRCncount = 0;
-                    }
-                    goto loadDone;     
+                    if(here -> VSRCdcGiven)
+                        value += here->VSRCdcValue;
                 } // case
                 break; 				
                 } // switch

src/spicelib/devices/vsrc/vsrcpar.c

@@ -11,6 +11,7 @@ Modified: 2000 AlansFixes
 #include "ifsim.h"
 #include "sperror.h"
 #include "suffix.h"
+#include "1-f-code.h"
 
 
 /* ARGSUSED */
@@ -169,12 +170,29 @@ VSRCparam(int param, IFvalue *value, GENinstance *inst, IFvalue *select)
 		    return(E_BADPARM);
 	    }
 	    break;
-        case VSRC_TRNOISE:
+        case VSRC_TRNOISE: {
+            double NA, TS;
+            double NALPHA = 0.0;
+            double NAMP   = 0.0;
+
             here->VSRCfunctionType = TRNOISE;
             here->VSRCfuncTGiven = TRUE;
             here->VSRCcoeffs = value->v.vec.rVec;
             here->VSRCfunctionOrder = value->v.numValue;
             here->VSRCcoeffsGiven = TRUE;
+
+            NA = here->VSRCcoeffs[0]; // input is rms value
+            TS = here->VSRCcoeffs[1]; // time step
+
+            if (here->VSRCfunctionOrder > 2)
+                NALPHA = here->VSRCcoeffs[2];
+
+            if (here->VSRCfunctionOrder > 3 && NALPHA != 0.0)
+                NAMP = here->VSRCcoeffs[3];
+
+            here->VSRCtrnoise_state =
+                trnoise_state_init(NA, TS, NALPHA, NAMP);
+        }
             break;		
         default:
             return(E_BADPARM);