# ftp.nice.ch/pub/next/unix/developer/plplot.3.0.s.tar.gz#/plplot/src/plzbx.c

```/* This draws a vertical line from (wx,wy1) to (wx,wy2)           */
/*  which represents the vertical axis of a 3-d graph with data   */
/*  values from "vmin" to "vmax". Depending on "opt", ticks and/or*/
/*  subticks are placed on the line at major tick interval "tick" */
/*  with "nsub" subticks between major ticks. If "tick" and/or    */
/*  "nsub" is zero, automatic tick positions are computed         */

/* B: Draws left-hand axis*/
/* C: Draws right-hand axis*/
/* I: Inverts tick marks (i.e. drawn to the left)  */
/* L: Logarithmic axes, major ticks at decades, minor ticks at units*/
/* M: Write numeric label on right axis*/
/* N: Write numeric label on left axis*/
/* S: Draw minor tick marks  */
/* T: Draw major tick marks  */
/* U: Writes left-hand label*/
/* V: Writes right-hand label*/

#include "plplot.h"
#include <stdio.h>
#include <math.h>

#define BETW(c,a,b) ((a <= c && c <= b) || (b <= c && c <= a))

static double xlog[8] =
{0.301030,0.477121,0.602060,0.698970,0.778151,0.845098,
0.903090,0.954243};

void plzbx(opt,label,right,dx,dy,wx,wy1,wy2,vmin,vmax,tick,nsub)
char *opt, *label;
double dx, dy, wx, wy1, wy2, vmin, vmax, tick;
int nsub, right;
{
static char string[40];
int lb,lc,li,ll,lm,ln,ls,lt,lu,lv;
int i, mode, prec, scal;
int nsub1;
double xpmm, ypmm, defmaj, defmin, tick1;
double pos, tn, tp, temp;
double dwy, lambda, diag, major, minor, xmajor, xminor;
double ymajor, yminor, dxm, dym, xscl, xoff, yscl, yoff;

dwy = wy2 - wy1;

/* Tick and subtick sizes in device coords */

gpixmm(&xpmm,&ypmm);
gmaj(&defmaj,&major);
gmin(&defmin,&minor);

tick1=tick;
nsub1=nsub;

lb=stsearch(opt,'b');
lc=stsearch(opt,'c');
li=stsearch(opt,'i');
ll=stsearch(opt,'l');
lm=stsearch(opt,'m');
ln=stsearch(opt,'n');
ls=stsearch(opt,'s');
lt=stsearch(opt,'t');
lu=stsearch(opt,'u');
lv=stsearch(opt,'v');

if (lu && !right)
plztx("h",dx,dy,wx,wy1,wy2,5.0,0.5,0.5,label);
if (lv && right)
plztx("h",dx,dy,wx,wy1,wy2,-5.0,0.5,0.5,label);

if (right && !lc)
return;
if (!right && !lb)
return;

if (ll)
tick1 = 1.0;
if (lt)
pldtik(vmin,vmax,&tick1,&nsub1,&mode,&prec,&scal);

if ( (li && !right) || (!li && right) ) {
minor = -minor;
major = -major;
}

gwm(&xscl,&xoff,&yscl,&yoff);
dxm = dx * xscl;
dym = dy * yscl;
diag = sqrt(dxm*dxm + dym*dym);

xminor = minor * dxm/diag;
xmajor = major * dxm/diag;
yminor = minor * dym/diag;
ymajor = major * dym/diag;

/* Draw the line */

movwor(wx,wy1);
if (lt) {
tp=tick1*floor(vmin/tick1);
for(;;) {
tn=tp+tick1;
if (ls) {
if (ll) {
for (i=0; i <= 7; i++) {
temp=tp+xlog[i];
if (BETW(temp,vmin,vmax)) {
lambda = (temp-vmin)/(vmax-vmin);
plstik(wcmmx(wx),wcmmy(wy1+lambda*dwy),xminor,yminor);
}
}
}
else  {
for (i=1; i<= nsub1-1; i++)  {
temp=tp+i*tick1/nsub1;
if (BETW(temp,vmin,vmax)) {
lambda = (temp-vmin)/(vmax-vmin);
plstik(wcmmx(wx),wcmmy(wy1+lambda*dwy),xminor,yminor);
}
}
}
}
temp=tn;
if (!BETW(temp,vmin,vmax))
break;
lambda = (temp-vmin)/(vmax-vmin);
plstik(wcmmx(wx),wcmmy((wy1+lambda*dwy)),xmajor,ymajor);
tp=tn;
}
}

drawor(wx,wy2);

/* Label the line */

if (ln && lt) {
tp=tick1*floor(vmin/tick1);
for(tn=tp+tick1; BETW(tn,vmin,vmax); tn+=tick1) {
if (!ll)
plform(tn,scal,prec,string);
else
sprintf(string,"10#u%d",round(tn));
pos=(tn-vmin)/(vmax-vmin);
if (ln && !right)
plztx("v",dx,dy,wx,wy1,wy2,0.5,pos,1.0,string);
if (lm && right)
plztx("v",dx,dy,wx,wy1,wy2,-0.5,pos,0.0,string);
}
if(!ll && mode) {
sprintf(string,"E%+d",scal);
if (ln && !right)
plztx("v",dx,dy,wx,wy1,wy2,0.5,1.0,1.0,string);
if (lm && right)
plztx("v",dx,dy,wx,wy1,wy2,-0.5,1.0,0.0,string);
}
}
}
```

These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.