struct PSpage {

	static FILE *PLT;
	static char *file;
	char fontname[128];
	Doub fontsize;

	PSpage(char *filnam) {
		file = new char[128];
		strcpy(file,filnam);
		PLT = fopen(file,"wb");
		if (!PLT) throw("failure opening output file for plot");
		fprintf(PLT,"%%!\n/mt{moveto}def /lt{lineto}def /np{newpath}def\n");
		fprintf(PLT,"/st{stroke}def /cp{closepath}def /fi{fill}def\n");
		fprintf(PLT,"/zp {gsave /ZapfDingbats findfont exch ");
		fprintf(PLT,"scalefont setfont moveto show grestore} def\n");
		setfont("Times-Roman",12.);
		setlinewidth(0.5);
	}
	PSpage() {}
	~PSpage() {if (PLT) close();}

	void setfont(char *fontnam, Doub size) {
		strcpy(fontname,fontnam);
		fontsize = size;
		fprintf(PLT,"/%s findfont %g scalefont setfont\n",fontnam,size);
	}

	void setcolor(Int r, Int g, Int b) {
		fprintf(PLT,"%g %g %g setrgbcolor\n",r/255.,g/255.,b/255.);}

	void setdash(char *patt, Int phase=0) {
		fprintf(PLT,"[%s] %d setdash\n",patt,phase);}

	void setlinewidth(Doub w) {fprintf(PLT,"%g setlinewidth\n",w);}

	void setgray(Doub w) {fprintf(PLT,"%g setgray\n",w);}

	void gsave() {fprintf(PLT,"gsave\n");}

	void grestore() {fprintf(PLT,"grestore\n");}

	void rawps(char *text) {fprintf(PLT,"%s\n",text);}

	void addtext(char *text) { fprintf(PLT,"(%s) show ",text); }

	void puttext(char *text, Doub x, Doub y, Doub rot=0.0) {
		fprintf(PLT,"gsave %g %g translate %g rotate 0 0 mt ",x,y,rot);
		addtext(text);
		fprintf(PLT,"grestore \n");
	}

	void putctext(char *text, Doub x, Doub y, Doub rot=0.0) {
		fprintf(PLT,"gsave %g %g translate %g rotate 0 0 mt (%s) ",x,y,rot,text);
		fprintf(PLT,"dup stringwidth pop 2 div neg 0 rmoveto show grestore\n");
	}

	void putrtext(char *text, Doub x, Doub y, Doub rot=0.0) {
		fprintf(PLT,"gsave %g %g translate %g rotate 0 0 mt (%s) ",x,y,rot,text);
		fprintf(PLT,"dup stringwidth pop neg 0 rmoveto show grestore\n");
	}

	void close() {fprintf(PLT,"showpage\n"); fclose(PLT); PLT = NULL;}

	void display() {
		char cmd[128];
		if (PLT) close();
		strcpy(cmd,"\"C:\\Program Files\\Ghostgum\\gsview\\gsview32.exe\" ");
		strcat(cmd,file);
		system(cmd);
	}

	void pointsymbol(Doub x, Doub y, Int num, double size) {
		fprintf(PLT,"(\\%03o) %g %g %g zp\n",num,x-0.394*size,y-0.343*size,size);
	}

	void lineseg(Doub xs, Doub ys, Doub xf, Doub yf) {
		fprintf(PLT,"np %g %g mt %g %g lt st\n",xs,ys,xf,yf);
	}

	void polyline(VecDoub &x, VecDoub &y, Int close=0, Int fill=0, Int clip=0) {
		Int i,n=MIN(x.size(),y.size());
		fprintf(PLT,"np %g %g mt\n",x[0],y[0]);
		for (i=1;i<n;i++) fprintf(PLT,"%g %g lt\n",x[i],y[i]);
		if (close || fill || clip) fprintf(PLT,"cp ");
		if (fill) fprintf(PLT,"fi\n");
		else if (clip) fprintf(PLT,"clip\n");
		else fprintf(PLT,"st\n");
	}
};

struct PSplot : PSpage {

	Doub pll,qll,pur,qur;
	Doub xll,yll,xur,yur;
	VecDoub xbox,ybox;
	Doub majticsz,minticsz;

	PSplot(PSpage &page, Doub ppll, Doub ppur, Doub qqll, Doub qqur)
		: pll(ppll), qll(qqll), pur(ppur), qur(qqur),
		xll(ppll), yll(qqll), xur(ppur), yur(qqur), xbox(4), ybox(4),
		majticsz(8.), minticsz(4.) {
			strcpy(fontname,page.fontname);
			fontsize = page.fontsize;
			setlimits(xll,xur,yll,yur);
		}

	Doub p(Doub x) {return pll + (pur-pll)*(x-xll)/(xur-xll);}
	Doub q(Doub y) {return qll + (qur-qll)*(y-yll)/(yur-yll);}
	
	void setlimits(Doub xxll, Doub xxur, Doub yyll, Doub yyur) {
		xbox[0] = xbox[3] = xll = xxll; ybox[0] = ybox[1] = yll = yyll;
		xbox[1] = xbox[2] = xur = xxur; ybox[2] = ybox[3] = yur = yyur;
	}
	
	void lineseg(Doub xs, Doub ys, Doub xf, Doub yf) {
		PSpage::lineseg(p(xs),q(ys),p(xf),q(yf));
	}
	
	void polyline(VecDoub &x, VecDoub &y, Int close=0, Int fill=0, Int clip=0) {
		Int i;
		VecDoub xx(x), yy(y);
		for (i=0;i<x.size();i++) xx[i] = p(x[i]);
		for (i=0;i<y.size();i++) yy[i] = q(y[i]);
		PSpage::polyline(xx,yy,close,fill,clip);
	}
	
	void dot(Doub x, Doub y, Doub size=2.) {
		PSpage::pointsymbol(p(x),q(y),108,size);
	}
	
	void pointsymbol(Doub x, Doub y, Int num, double size) {
		PSpage::pointsymbol(p(x),q(y),num,size);
	}
	
	void lineplot(VecDoub &x, VecDoub &y) {polyline(x,y);}
	
	void frame() {polyline(xbox,ybox,1,0);}
	
	void clear() {gsave(); setgray(1.); polyline(xbox,ybox,1,1); grestore();}
	
	void clip() {gsave(); polyline(xbox,ybox,1,0,1);}
	
	void clip(VecDoub &x, VecDoub &y) {gsave(); polyline(x,y,1,0,1);}
	
	void unclip() {grestore();}
	
	void xlabel(char *text) {putctext(text,0.5*(pll+pur),qll-2.*fontsize-8.);}
	
	void ylabel(char *text) {putctext(text,pll-3.*fontsize-8.,0.5*(qll+qur),90.);}
	
	void label(char *text, double x, double y, double rot=0.) {puttext(text,p(x),q(y),rot);}
	
	void scalestr(char *str, double x) {
		if (abs(x) < 1.e-15) x = 0.;
		sprintf(str,"%g",x);
	}
	
	void scales(Doub xmajd, Doub xmind, Doub ymajd, Doub ymind,
	Int dox=2, Int doy=2, Int doxx=1, Int doyy=1) {
		char str[128];
		Doub x,y,xlo,ylo;
		if (dox || doxx) {
			xlo = ceil(MIN(xll,xur)/xmajd)*xmajd;
			for (x=xlo;x<=MAX(xll,xur);x+=xmajd) {
				scalestr(str,x);
				if (dox>1) putctext(str,p(x),qll-fontsize-2.);
				if (dox) PSpage::lineseg(p(x),qll,p(x),qll+majticsz);
				if (doxx) PSpage::lineseg(p(x),qur,p(x),qur-majticsz);
			}
			xlo = ceil(MIN(xll,xur)/xmind)*xmind;
			for (x=xlo;x<=MAX(xll,xur);x+=xmind) {
				if (dox) PSpage::lineseg(p(x),qll,p(x),qll+minticsz);
				if (doxx) PSpage::lineseg(p(x),qur,p(x),qur-minticsz);
			}
		}
		if (doy || doyy) {
			ylo = ceil(MIN(yll,yur)/ymajd)*ymajd;
			for (y=ylo;y<=MAX(yll,yur);y+=ymajd) {
				scalestr(str,y);
				if (doy>1) putrtext(str,pll-4.,q(y)-0.3*fontsize);
				if (doy) PSpage::lineseg(pll,q(y),pll+majticsz,q(y));
				if (doyy) PSpage::lineseg(pur,q(y),pur-majticsz,q(y));
			}
			ylo = ceil(MIN(yll,yur)/ymind)*ymind;
			for (y=ylo;y<=MAX(yll,yur);y+=ymind) {
				if (doy) PSpage::lineseg(pll,q(y),pll+minticsz,q(y));
				if (doyy) PSpage::lineseg(pur,q(y),pur-minticsz,q(y));
			}
		}
	}
	
	void autoscales() {
		double xmajd, xmind, ymajd, ymind;
		xmajd = pow(10.,((Int)(log10(abs(xur-xll))-1.1)));
		xmind = xmajd/5.;
		ymajd = pow(10.,((Int)(log10(abs(yur-yll))-1.1)));
		ymind = ymajd/5.;
		scales(xmajd,xmind,ymajd,ymind);
	}
};
FILE *PSpage::PLT;
char *PSpage::file;