--- /dev/null
+.\" $NetBSD: units.1,v 1.21 2013/07/20 21:40:01 wiz Exp $
+.Dd January 6, 2013
+.Dt UNITS 1
+.Os
+.Sh NAME
+.Nm units
+.Nd conversion program
+.Sh SYNOPSIS
+.Nm
+.Op Fl Llqv
+.Op Fl f Ar filename
+.Oo
+.Op Ar count
+.Ar from-unit to-unit
+.Oc
+.Sh DESCRIPTION
+.Nm
+converts quantities expression in various scales to
+their equivalents in other scales.
+.Nm
+can only handle multiplicative scale changes.
+It cannot convert Centigrade to Fahrenheit, for example.
+.Pp
+The following options and arguments are supported:
+.Bl -tag -width "-fXfilenameX" -offset indent
+.It Fl f Ar filename
+Specifies the name of the units data file to load.
+.It Fl l No or Fl L
+List all unit definitions to the standard output,
+instead of performing any conversions.
+The result may include error messages and comments, beginning with
+.Ql \&/ .
+.Pp
+With the
+.Fl l
+option, unit definitions will be listed in a format
+almost identical to the the units data file that was loaded,
+except that comments will be removed, spacing may be changed,
+and lines may be re-ordered.
+.Pp
+With the
+.Fl L
+option, all unit definitions will be reduced to a form that
+depends on only a few primitive units (such as
+.Sy m , kg , sec ) .
+.It Fl q
+Suppresses prompting of the user for units and the display of statistics
+about the number of units loaded.
+.It Fl v
+Prints the version number.
+.It Oo Ar count Oc Ar from-unit Ar to-unit
+Allows a single unit conversion to be done directly from the command
+line.
+No prompting will occur.
+.Nm
+will print out only the result of this single conversion.
+Specifying
+.Ar count
+and
+.Ar from-unit
+as two separate arguments is equivalent to embedding both parts
+inside a single
+.Ar from-unit
+argument, with the parts separated by a space.
+.El
+.Pp
+.Nm
+works interactively by prompting the user for input:
+.Bd -literal
+ You have: meters
+ You want: feet
+ * 3.2808399
+ / 0.3048
+
+ You have: cm^3
+ You want: gallons
+ * 0.00026417205
+ / 3785.4118
+.Ed
+.Pp
+Powers of units can be specified using the
+.Dq \&^
+character as shown in the example, or by simple concatenation:
+.Dq cm3
+is equivalent to
+.Dq cm^3 .
+Multiplication of units can be specified by using spaces, a dash or
+an asterisk.
+Division of units is indicated by the slash
+.Pq Sq \&/ .
+Note that multiplication has a higher precedence than division,
+so
+.Dq m/s/s
+is the same as
+.Dq m/s^2
+or
+.Dq "m/s s" .
+If the user enters incompatible unit types, the
+.Nm
+program will print a message indicating that the units are not
+conformable and it will display the reduced form for each unit:
+.Bd -literal
+ You have: ergs/hour
+ You want: fathoms kg^2 / day
+ conformability error
+ 2.7777778e-11 kg m^2 / sec^3
+ 2.1166667e-05 kg^2 m / sec
+.Ed
+.Pp
+The conversion information is read from a units data file.
+The default
+file includes definitions for most familiar units, abbreviations and
+metric prefixes.
+Some constants of nature included are:
+.Bl -tag -width mercury -compact -offset indent
+.It pi
+ratio of circumference to diameter
+.It c
+speed of light
+.It e
+charge on an electron
+.It g
+acceleration of gravity
+.It force
+same as g
+.It mole
+Avogadro's number
+.It water
+pressure per unit height of water
+.It mercury
+pressure per unit height of mercury
+.It au
+astronomical unit
+.El
+.Pp
+.Dq pound
+is a unit of mass.
+Compound names are run together
+so
+.Dq poundforce
+is a unit of force.
+British units that differ from their
+US counterparts are prefixed with
+.Dq br ,
+and currency is prefixed with
+its country name:
+.Dq belgiumfranc ,
+.Dq britainpound .
+When searching for
+a unit, if the specified string does not appear exactly as a unit
+name, then the
+.Nm
+program will try to remove a trailing
+.Dq s
+or a trailing
+.Dq es
+and check again for a match.
+.Pp
+All of these definitions can be read in the standard units file, or you
+can supply your own file.
+A unit is specified on a single line by
+giving its name and an equivalence.
+One should be careful to define
+new units in terms of old ones so that a reduction leads to the
+primitive units which are marked with
+.Sq \&!
+characters.
+.Nm
+will not detect infinite loops that could be caused
+by careless unit definitions.
+.Pp
+Prefixes are defined in the same way as standard units, but with
+a trailing dash at the end of the prefix name.
+.Sh FILES
+.Bl -tag -width /usr/share/misc/units.lib -compact
+.It Pa /usr/share/misc/units.lib
+the standard units library
+.El
+.Sh AUTHORS
+.An Adrian Mariano Aq Mt adrian@cam.cornell.edu
+or
+.Aq mariano@geom.umn.edu
+.Sh CAVEATS
+While
+.Nm
+can be used as a calculator for many unit-related computations,
+caution is required: many computations require additional constant
+factors deriving from the physics (or chemistry or whatever) of the
+situation.
+As these factors are dimensionless,
+.Nm
+cannot itself either provide them or warn the user when they have been
+forgotten.
+For example, one joule is one kilogram meter squared per second
+squared, by definition; however, the kinetic energy of a one-kilogram
+object moving at one meter per second is half a joule, not one joule,
+because of a dimensionless factor that arises from integration.
+.Pp
+Also, some pairs of units that have the same dimensionality are
+nonetheless used to measure different things and attempting to convert
+between them may require additional fudge factors or be entirely
+meaningless.
+For example, torque and energy have the same dimensionality, but
+attempting to convert torque in newton-meters to energy in joules is
+nonsensical.
+There is no practical way for
+.Nm
+to warn about these issues either.
+.Sh BUGS
+The effect of including a
+.Sq \&/
+in a prefix is surprising.
+.Pp
+Exponents entered by the user can be only one digit.
+You can work around this by multiplying several terms.
+.Pp
+The user must use
+.Sq \&|
+to indicate division of numbers and
+.Sq \&/
+to indicate division of symbols.
+This distinction should not be necessary.
+.Pp
+The program contains various arbitrary limits on the length
+of the units converted and on the length of the data file.
+.Pp
+The program should use a hash table to store units so that
+it doesn't take so long to load the units list and check
+for duplication.
--- /dev/null
+/* $NetBSD: units.c,v 1.24 2013/01/06 00:19:13 wiz Exp $ */
+
+/*
+ * units.c Copyright (c) 1993 by Adrian Mariano (adrian@cam.cornell.edu)
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. The name of the author may not be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ * Disclaimer: This software is provided by the author "as is". The author
+ * shall not be liable for any damages caused in any way by this software.
+ *
+ * I would appreciate (though I do not require) receiving a copy of any
+ * improvements you might make to this program.
+ */
+
+#include <ctype.h>
+#include <err.h>
+#include <float.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "pathnames.h"
+
+#define VERSION "1.0"
+
+#ifndef UNITSFILE
+#define UNITSFILE _PATH_UNITSLIB
+#endif
+
+#define MAXUNITS 1000
+#define MAXPREFIXES 50
+
+#define MAXSUBUNITS 500
+
+#define PRIMITIVECHAR '!'
+
+static int precision = 8; /* for printf with "%.*g" format */
+
+static const char *errprefix = NULL; /* if not NULL, then prepend this
+ * to error messages and send them to
+ * stdout instead of stderr.
+ */
+
+static const char *powerstring = "^";
+
+static struct {
+ const char *uname;
+ const char *uval;
+} unittable[MAXUNITS];
+
+struct unittype {
+ const char *numerator[MAXSUBUNITS];
+ const char *denominator[MAXSUBUNITS];
+ double factor;
+};
+
+struct {
+ const char *prefixname;
+ const char *prefixval;
+} prefixtable[MAXPREFIXES];
+
+
+static const char *NULLUNIT = "";
+
+static int unitcount;
+static int prefixcount;
+
+
+static int addsubunit(const char *[], const char *);
+static int addunit(struct unittype *, const char *, int);
+static void cancelunit(struct unittype *);
+static int compare(const void *, const void *);
+static int compareproducts(const char **, const char **);
+static int compareunits(struct unittype *, struct unittype *);
+static int compareunitsreciprocal(struct unittype *, struct unittype *);
+static int completereduce(struct unittype *);
+static void initializeunit(struct unittype *);
+static void readerror(int);
+static void readunits(const char *);
+static int reduceproduct(struct unittype *, int);
+static int reduceunit(struct unittype *);
+static void showanswer(struct unittype *, struct unittype *);
+static void showunit(struct unittype *);
+static void sortunit(struct unittype *);
+__dead static void usage(void);
+static void zeroerror(void);
+static char *dupstr(const char *);
+static const char *lookupunit(const char *);
+
+static char *
+dupstr(const char *str)
+{
+ char *ret;
+
+ ret = strdup(str);
+ if (!ret)
+ err(3, "Memory allocation error");
+ return (ret);
+}
+
+
+static void
+mywarnx(const char *fmt, ...)
+{
+ va_list args;
+
+ va_start(args, fmt);
+ if (errprefix) {
+ /* warn to stdout, with errprefix prepended */
+ printf("%s", errprefix);
+ vprintf(fmt, args);
+ printf("%s", "\n");
+ } else {
+ /* warn to stderr */
+ vwarnx(fmt, args);
+ }
+ va_end(args);
+}
+
+static void
+readerror(int linenum)
+{
+ mywarnx("Error in units file '%s' line %d", UNITSFILE, linenum);
+}
+
+
+static void
+readunits(const char *userfile)
+{
+ FILE *unitfile;
+ char line[80], *lineptr;
+ int len, linenum, i, isdup;
+
+ unitcount = 0;
+ linenum = 0;
+
+ if (userfile) {
+ unitfile = fopen(userfile, "rt");
+ if (!unitfile)
+ err(1, "Unable to open units file '%s'", userfile);
+ }
+ else {
+ unitfile = fopen(UNITSFILE, "rt");
+ if (!unitfile) {
+ char *direc, *env;
+ char filename[1000];
+ char separator[2];
+
+ env = getenv("PATH");
+ if (env) {
+ if (strchr(env, ';'))
+ strlcpy(separator, ";",
+ sizeof(separator));
+ else
+ strlcpy(separator, ":",
+ sizeof(separator));
+ direc = strtok(env, separator);
+ while (direc) {
+ strlcpy(filename, "", sizeof(filename));
+ strlcat(filename, direc,
+ sizeof(filename));
+ strlcat(filename, "/",
+ sizeof(filename));
+ strlcat(filename, UNITSFILE,
+ sizeof(filename));
+ unitfile = fopen(filename, "rt");
+ if (unitfile)
+ break;
+ direc = strtok(NULL, separator);
+ }
+ }
+ if (!unitfile)
+ errx(1, "Can't find units file '%s'",
+ UNITSFILE);
+ }
+ }
+ while (!feof(unitfile)) {
+ if (!fgets(line, 79, unitfile))
+ break;
+ linenum++;
+ lineptr = line;
+ if (*lineptr == '/')
+ continue;
+ lineptr += strspn(lineptr, " \n\t");
+ len = strcspn(lineptr, " \n\t");
+ lineptr[len] = 0;
+ if (!strlen(lineptr))
+ continue;
+ if (lineptr[strlen(lineptr) - 1] == '-') { /* it's a prefix */
+ if (prefixcount == MAXPREFIXES) {
+ mywarnx(
+ "Memory for prefixes exceeded in line %d",
+ linenum);
+ continue;
+ }
+ lineptr[strlen(lineptr) - 1] = 0;
+ for (isdup = 0, i = 0; i < prefixcount; i++) {
+ if (!strcmp(prefixtable[i].prefixname,
+ lineptr)) {
+ isdup = 1;
+ break;
+ }
+ }
+ if (isdup) {
+ mywarnx(
+ "Redefinition of prefix '%s' on line %d ignored",
+ lineptr, linenum);
+ continue;
+ }
+ prefixtable[prefixcount].prefixname = dupstr(lineptr);
+ lineptr += len + 1;
+ if (!strlen(lineptr)) {
+ readerror(linenum);
+ continue;
+ }
+ lineptr += strspn(lineptr, " \n\t");
+ len = strcspn(lineptr, "\n\t");
+ lineptr[len] = 0;
+ prefixtable[prefixcount++].prefixval = dupstr(lineptr);
+ }
+ else { /* it's not a prefix */
+ if (unitcount == MAXUNITS) {
+ mywarnx("Memory for units exceeded in line %d",
+ linenum);
+ continue;
+ }
+ for (isdup = 0, i = 0; i < unitcount; i++) {
+ if (!strcmp(unittable[i].uname, lineptr)) {
+ isdup = 1;
+ break;
+ }
+ }
+ if (isdup) {
+ mywarnx(
+ "Redefinition of unit '%s' on line %d ignored",
+ lineptr, linenum);
+ continue;
+ }
+ unittable[unitcount].uname = dupstr(lineptr);
+ lineptr += len + 1;
+ lineptr += strspn(lineptr, " \n\t");
+ if (!strlen(lineptr)) {
+ readerror(linenum);
+ continue;
+ }
+ len = strcspn(lineptr, "\n\t");
+ lineptr[len] = 0;
+ unittable[unitcount++].uval = dupstr(lineptr);
+ }
+ }
+ fclose(unitfile);
+}
+
+static void
+initializeunit(struct unittype * theunit)
+{
+ theunit->factor = 1.0;
+ theunit->numerator[0] = theunit->denominator[0] = NULL;
+}
+
+static int
+addsubunit(const char *product[], const char *toadd)
+{
+ const char **ptr;
+
+ for (ptr = product; *ptr && *ptr != NULLUNIT; ptr++);
+ if (ptr >= product + MAXSUBUNITS) {
+ mywarnx("Memory overflow in unit reduction");
+ return 1;
+ }
+ if (!*ptr)
+ *(ptr + 1) = 0;
+ *ptr = dupstr(toadd);
+ return 0;
+}
+
+static void
+showunit(struct unittype * theunit)
+{
+ const char **ptr;
+ int printedslash;
+ int counter = 1;
+
+ printf("\t%.*g", precision, theunit->factor);
+ for (ptr = theunit->numerator; *ptr; ptr++) {
+ if (ptr > theunit->numerator && **ptr &&
+ !strcmp(*ptr, *(ptr - 1)))
+ counter++;
+ else {
+ if (counter > 1)
+ printf("%s%d", powerstring, counter);
+ if (**ptr)
+ printf(" %s", *ptr);
+ counter = 1;
+ }
+ }
+ if (counter > 1)
+ printf("%s%d", powerstring, counter);
+ counter = 1;
+ printedslash = 0;
+ for (ptr = theunit->denominator; *ptr; ptr++) {
+ if (ptr > theunit->denominator && **ptr &&
+ !strcmp(*ptr, *(ptr - 1)))
+ counter++;
+ else {
+ if (counter > 1)
+ printf("%s%d", powerstring, counter);
+ if (**ptr) {
+ if (!printedslash)
+ printf(" /");
+ printedslash = 1;
+ printf(" %s", *ptr);
+ }
+ counter = 1;
+ }
+ }
+ if (counter > 1)
+ printf("%s%d", powerstring, counter);
+ printf("\n");
+}
+
+static void
+zeroerror(void)
+{
+ mywarnx("Unit reduces to zero");
+}
+
+/*
+ Adds the specified string to the unit.
+ Flip is 0 for adding normally, 1 for adding reciprocal.
+
+ Returns 0 for successful addition, nonzero on error.
+*/
+
+static int
+addunit(struct unittype * theunit, const char *toadd, int flip)
+{
+ char *scratch, *savescr;
+ char *item;
+ char *divider, *slash;
+ int doingtop;
+
+ savescr = scratch = dupstr(toadd);
+ for (slash = scratch + 1; *slash; slash++)
+ if (*slash == '-' &&
+ (tolower((unsigned char)*(slash - 1)) != 'e' ||
+ !strchr(".0123456789", *(slash + 1))))
+ *slash = ' ';
+ slash = strchr(scratch, '/');
+ if (slash)
+ *slash = 0;
+ doingtop = 1;
+ do {
+ item = strtok(scratch, " *\t\n/");
+ while (item) {
+ if (strchr("0123456789.", *item)) {
+ /* item starts with a number */
+ char *endptr;
+ double num;
+
+ divider = strchr(item, '|');
+ if (divider) {
+ *divider = 0;
+ num = strtod(item, &endptr);
+ if (!num) {
+ zeroerror();
+ return 1;
+ }
+ if (endptr != divider) {
+ /* "6foo|2" is an error */
+ mywarnx("Junk before '|'");
+ return 1;
+ }
+ if (doingtop ^ flip)
+ theunit->factor *= num;
+ else
+ theunit->factor /= num;
+ num = strtod(divider + 1, &endptr);
+ if (!num) {
+ zeroerror();
+ return 1;
+ }
+ if (doingtop ^ flip)
+ theunit->factor /= num;
+ else
+ theunit->factor *= num;
+ if (*endptr) {
+ /* "6|2foo" is like "6|2 foo" */
+ item = endptr;
+ continue;
+ }
+ }
+ else {
+ num = strtod(item, &endptr);
+ if (!num) {
+ zeroerror();
+ return 1;
+ }
+ if (doingtop ^ flip)
+ theunit->factor *= num;
+ else
+ theunit->factor /= num;
+ if (*endptr) {
+ /* "3foo" is like "3 foo" */
+ item = endptr;
+ continue;
+ }
+ }
+ }
+ else { /* item is not a number */
+ int repeat = 1;
+
+ if (strchr("23456789",
+ item[strlen(item) - 1])) {
+ repeat = item[strlen(item) - 1] - '0';
+ item[strlen(item) - 1] = 0;
+ }
+ for (; repeat; repeat--)
+ if (addsubunit(doingtop ^ flip ? theunit->numerator : theunit->denominator, item))
+ return 1;
+ }
+ item = strtok(NULL, " *\t/\n");
+ }
+ doingtop--;
+ if (slash) {
+ scratch = slash + 1;
+ }
+ else
+ doingtop--;
+ } while (doingtop >= 0);
+ free(savescr);
+ return 0;
+}
+
+static int
+compare(const void *item1, const void *item2)
+{
+ return strcmp(*(const char * const *) item1,
+ *(const char * const *) item2);
+}
+
+static void
+sortunit(struct unittype * theunit)
+{
+ const char **ptr;
+ int count;
+
+ for (count = 0, ptr = theunit->numerator; *ptr; ptr++, count++);
+ qsort(theunit->numerator, count, sizeof(char *), compare);
+ for (count = 0, ptr = theunit->denominator; *ptr; ptr++, count++);
+ qsort(theunit->denominator, count, sizeof(char *), compare);
+}
+
+static void
+cancelunit(struct unittype * theunit)
+{
+ const char **den, **num;
+ int comp;
+
+ den = theunit->denominator;
+ num = theunit->numerator;
+
+ while (*num && *den) {
+ comp = strcmp(*den, *num);
+ if (!comp) {
+/* if (*den!=NULLUNIT) free(*den);
+ if (*num!=NULLUNIT) free(*num);*/
+ *den++ = NULLUNIT;
+ *num++ = NULLUNIT;
+ }
+ else if (comp < 0)
+ den++;
+ else
+ num++;
+ }
+}
+
+
+
+
+/*
+ Looks up the definition for the specified unit.
+ Returns a pointer to the definition or a null pointer
+ if the specified unit does not appear in the units table.
+*/
+
+static char buffer[100]; /* buffer for lookupunit answers with
+ prefixes */
+
+static const char *
+lookupunit(const char *unit)
+{
+ int i;
+ char *copy;
+
+ for (i = 0; i < unitcount; i++) {
+ if (!strcmp(unittable[i].uname, unit))
+ return unittable[i].uval;
+ }
+
+ if (unit[strlen(unit) - 1] == '^') {
+ copy = dupstr(unit);
+ copy[strlen(copy) - 1] = 0;
+ for (i = 0; i < unitcount; i++) {
+ if (!strcmp(unittable[i].uname, copy)) {
+ strlcpy(buffer, copy, sizeof(buffer));
+ free(copy);
+ return buffer;
+ }
+ }
+ free(copy);
+ }
+ if (unit[strlen(unit) - 1] == 's') {
+ copy = dupstr(unit);
+ copy[strlen(copy) - 1] = 0;
+ for (i = 0; i < unitcount; i++) {
+ if (!strcmp(unittable[i].uname, copy)) {
+ strlcpy(buffer, copy, sizeof(buffer));
+ free(copy);
+ return buffer;
+ }
+ }
+ if (copy[strlen(copy) - 1] == 'e') {
+ copy[strlen(copy) - 1] = 0;
+ for (i = 0; i < unitcount; i++) {
+ if (!strcmp(unittable[i].uname, copy)) {
+ strlcpy(buffer, copy, sizeof(buffer));
+ free(copy);
+ return buffer;
+ }
+ }
+ }
+ free(copy);
+ }
+ for (i = 0; i < prefixcount; i++) {
+ if (!strncmp(prefixtable[i].prefixname, unit,
+ strlen(prefixtable[i].prefixname))) {
+ unit += strlen(prefixtable[i].prefixname);
+ if (!strlen(unit) || lookupunit(unit)) {
+ strlcpy(buffer, prefixtable[i].prefixval,
+ sizeof(buffer));
+ strlcat(buffer, " ", sizeof(buffer));
+ strlcat(buffer, unit, sizeof(buffer));
+ return buffer;
+ }
+ }
+ }
+ return 0;
+}
+
+
+
+/*
+ reduces a product of symbolic units to primitive units.
+ The three low bits are used to return flags:
+
+ bit 0 (1) set on if reductions were performed without error.
+ bit 1 (2) set on if no reductions are performed.
+ bit 2 (4) set on if an unknown unit is discovered.
+*/
+
+
+#define ERROR 4
+
+static int
+reduceproduct(struct unittype * theunit, int flip)
+{
+
+ const char *toadd;
+ const char **product;
+ int didsomething = 2;
+
+ if (flip)
+ product = theunit->denominator;
+ else
+ product = theunit->numerator;
+
+ for (; *product; product++) {
+
+ for (;;) {
+ if (!strlen(*product))
+ break;
+ toadd = lookupunit(*product);
+ if (!toadd) {
+ mywarnx("Unknown unit '%s'", *product);
+ return ERROR;
+ }
+ if (strchr(toadd, PRIMITIVECHAR))
+ break;
+ didsomething = 1;
+ if (*product != NULLUNIT) {
+ free(__UNCONST(*product));
+ *product = NULLUNIT;
+ }
+ if (addunit(theunit, toadd, flip))
+ return ERROR;
+ }
+ }
+ return didsomething;
+}
+
+
+/*
+ Reduces numerator and denominator of the specified unit.
+ Returns 0 on success, or 1 on unknown unit error.
+*/
+
+static int
+reduceunit(struct unittype * theunit)
+{
+ int ret;
+
+ ret = 1;
+ while (ret & 1) {
+ ret = reduceproduct(theunit, 0) | reduceproduct(theunit, 1);
+ if (ret & 4)
+ return 1;
+ }
+ return 0;
+}
+
+static int
+compareproducts(const char **one, const char **two)
+{
+ while (*one || *two) {
+ if (!*one && *two != NULLUNIT)
+ return 1;
+ if (!*two && *one != NULLUNIT)
+ return 1;
+ if (*one == NULLUNIT)
+ one++;
+ else if (*two == NULLUNIT)
+ two++;
+ else if (*one && *two && strcmp(*one, *two))
+ return 1;
+ else
+ one++, two++;
+ }
+ return 0;
+}
+
+
+/* Return zero if units are compatible, nonzero otherwise */
+
+static int
+compareunits(struct unittype * first, struct unittype * second)
+{
+ return
+ compareproducts(first->numerator, second->numerator) ||
+ compareproducts(first->denominator, second->denominator);
+}
+
+static int
+compareunitsreciprocal(struct unittype * first, struct unittype * second)
+{
+ return
+ compareproducts(first->numerator, second->denominator) ||
+ compareproducts(first->denominator, second->numerator);
+}
+
+
+static int
+completereduce(struct unittype * unit)
+{
+ if (reduceunit(unit))
+ return 1;
+ sortunit(unit);
+ cancelunit(unit);
+ return 0;
+}
+
+
+static void
+showanswer(struct unittype * have, struct unittype * want)
+{
+ if (compareunits(have, want)) {
+ if (compareunitsreciprocal(have, want)) {
+ printf("conformability error\n");
+ showunit(have);
+ showunit(want);
+ } else {
+ printf("\treciprocal conversion\n");
+ printf("\t* %.*g\n\t/ %.*g\n",
+ precision, 1 / (have->factor * want->factor),
+ precision, want->factor * have->factor);
+ }
+ }
+ else
+ printf("\t* %.*g\n\t/ %.*g\n",
+ precision, have->factor / want->factor,
+ precision, want->factor / have->factor);
+}
+
+static int
+listunits(int expand)
+{
+ struct unittype theunit;
+ const char *thename;
+ const char *thedefn;
+ int errors = 0;
+ int i;
+ int printexpansion;
+
+ /*
+ * send error and warning messages to stdout,
+ * and make them look like comments.
+ */
+ errprefix = "/ ";
+
+#if 0 /* debug */
+ printf("/ expand=%d precision=%d unitcount=%d prefixcount=%d\n",
+ expand, precision, unitcount, prefixcount);
+#endif
+
+ /* 1. Dump all primitive units, e.g. "m !a!", "kg !b!", ... */
+ printf("/ Primitive units\n");
+ for (i = 0; i < unitcount; i++) {
+ thename = unittable[i].uname;
+ thedefn = unittable[i].uval;
+ if (thedefn[0] == PRIMITIVECHAR) {
+ printf("%s\t%s\n", thename, thedefn);
+ }
+ }
+
+ /* 2. Dump all prefixes, e.g. "yotta- 1e24", "zetta- 1e21", ... */
+ printf("/ Prefixes\n");
+ for (i = 0; i < prefixcount; i++) {
+ printexpansion = expand;
+ thename = prefixtable[i].prefixname;
+ thedefn = prefixtable[i].prefixval;
+ if (expand) {
+ /*
+ * prefix names are sometimes identical to unit
+ * names, so we have to expand thedefn instead of
+ * expanding thename.
+ */
+ initializeunit(&theunit);
+ if (addunit(&theunit, thedefn, 0) != 0
+ || completereduce(&theunit) != 0) {
+ errors++;
+ printexpansion = 0;
+ mywarnx("Error in prefix '%s-'", thename);
+ }
+ }
+ if (printexpansion) {
+ printf("%s-", thename);
+ showunit(&theunit);
+ } else
+ printf("%s-\t%s\n", thename, thedefn);
+ }
+
+ /* 3. Dump all other units. */
+ printf("/ Other units\n");
+ for (i = 0; i < unitcount; i++) {
+ printexpansion = expand;
+ thename = unittable[i].uname;
+ thedefn = unittable[i].uval;
+ if (thedefn[0] == PRIMITIVECHAR)
+ continue;
+ if (expand) {
+ /*
+ * expand thename, not thedefn, so that
+ * we can catch errors in the name itself.
+ * e.g. a name that contains a hyphen
+ * will be interpreted as multiplication.
+ */
+ initializeunit(&theunit);
+ if (addunit(&theunit, thename, 0) != 0
+ || completereduce(&theunit) != 0) {
+ errors++;
+ printexpansion = 0;
+ mywarnx("Error in unit '%s'", thename);
+ }
+ }
+ if (printexpansion) {
+ printf("%s", thename);
+ showunit(&theunit);
+ } else
+ printf("%s\t%s\n", thename, thedefn);
+ }
+
+ if (errors)
+ mywarnx("Definitions with errors: %d", errors);
+ return (errors ? 1 : 0);
+}
+
+static void
+usage(void)
+{
+ fprintf(stderr,
+ "\nunits [-Llqv] [-f filename] [[count] from-unit to-unit]\n");
+ fprintf(stderr, "\n -f specify units file\n");
+ fprintf(stderr, " -L list units in standardized base units\n");
+ fprintf(stderr, " -l list units\n");
+ fprintf(stderr, " -q suppress prompting (quiet)\n");
+ fprintf(stderr, " -v print version number\n");
+ exit(3);
+}
+
+int
+main(int argc, char **argv)
+{
+
+ struct unittype have, want;
+ char havestr[81], wantstr[81];
+ int optchar;
+ const char *userfile = 0;
+ int list = 0, listexpand = 0;
+ int quiet = 0;
+
+ while ((optchar = getopt(argc, argv, "lLvqf:")) != -1) {
+ switch (optchar) {
+ case 'l':
+ list = 1;
+ break;
+ case 'L':
+ list = 1;
+ listexpand = 1;
+ precision = DBL_DIG;
+ break;
+ case 'f':
+ userfile = optarg;
+ break;
+ case 'q':
+ quiet = 1;
+ break;
+ case 'v':
+ fprintf(stderr, "\n units version %s Copyright (c) 1993 by Adrian Mariano\n",
+ VERSION);
+ fprintf(stderr, " This program may be freely distributed\n");
+ usage();
+ default:
+ usage();
+ break;
+ }
+ }
+
+ argc -= optind;
+ argv += optind;
+
+ if ((argc != 3 && argc != 2 && argc != 0)
+ || (list && argc != 0))
+ usage();
+
+ if (list)
+ errprefix = "/ "; /* set this before reading the file */
+
+ readunits(userfile);
+
+ if (list)
+ return listunits(listexpand);
+
+ if (argc == 3) {
+ strlcpy(havestr, argv[0], sizeof(havestr));
+ strlcat(havestr, " ", sizeof(havestr));
+ strlcat(havestr, argv[1], sizeof(havestr));
+ argc--;
+ argv++;
+ argv[0] = havestr;
+ }
+
+ if (argc == 2) {
+ strlcpy(havestr, argv[0], sizeof(havestr));
+ strlcpy(wantstr, argv[1], sizeof(wantstr));
+ initializeunit(&have);
+ addunit(&have, havestr, 0);
+ completereduce(&have);
+ initializeunit(&want);
+ addunit(&want, wantstr, 0);
+ completereduce(&want);
+ showanswer(&have, &want);
+ }
+ else {
+ if (!quiet)
+ printf("%d units, %d prefixes\n\n", unitcount,
+ prefixcount);
+ for (;;) {
+ do {
+ initializeunit(&have);
+ if (!quiet)
+ printf("You have: ");
+ if (!fgets(havestr, 80, stdin)) {
+ if (!quiet)
+ putchar('\n');
+ exit(0);
+ }
+ } while (addunit(&have, havestr, 0) ||
+ completereduce(&have));
+ do {
+ initializeunit(&want);
+ if (!quiet)
+ printf("You want: ");
+ if (!fgets(wantstr, 80, stdin)) {
+ if (!quiet)
+ putchar('\n');
+ exit(0);
+ }
+ } while (addunit(&want, wantstr, 0) ||
+ completereduce(&want));
+ showanswer(&have, &want);
+ }
+ }
+ return (0);
+}
--- /dev/null
+/ $NetBSD: units.lib,v 1.17 2012/12/28 17:57:46 apb Exp $
+
+/ primitive units
+
+m !a!
+kg !b!
+sec !c!
+coul !d!
+candela !e!
+dollar !f!
+bit !h!
+erlang !i!
+K !j!
+
+/ prefixes
+
+yotta- 1e24
+zetta- 1e21
+exa- 1e18
+peta- 1e15
+tera- 1e12
+giga- 1e9
+mega- 1e6
+myria- 1e4
+kilo- 1e3
+hecto- 1e2
+deka- 1e1
+deci- 1e-1
+centi- 1e-2
+milli- 1e-3
+micro- 1e-6
+nano- 1e-9
+pico- 1e-12
+femto- 1e-15
+atto- 1e-18
+zopto- 1e-21
+yocto- 1e-24
+
+semi- .5
+demi- .5
+
+Y- yotta
+Z- zetta
+E- exa
+P- peta
+T- tera
+G- giga
+M- mega
+k- kilo
+h- hecto
+da- deka
+d- deci
+c- centi
+m- milli
+p- pico
+f- femto
+a- atto
+z- zopto
+y- yocto
+
+/ constants
+
+fuzz 1
+pi 3.14159265358979323846
+c 2.99792458e+8 m/sec fuzz
+g 9.80665 m/sec2
+au 1.49597871e+11 m fuzz
+mole 6.022169e+23 fuzz
+e 1.6021917e-19 coul fuzz
+energy c2
+force g
+mercury 1.33322e+5 kg/m2-sec2
+hg mercury
+
+/ dimensionless
+
+radian .5 / pi
+degree 1|180 pi-radian
+circle 2 pi-radian
+turn 2 pi-radian
+revolution turn
+rev turn
+grade .9 degree
+arcdeg 1 degree
+arcmin 1|60 arcdeg
+ccs 1|36 erlang
+arcsec 1|60 arcmin
+
+steradian radian2
+sphere 4 pi-steradian
+sr steradian
+
+/ Time
+
+second sec
+s sec
+minute 60 sec
+min minute
+hour 60 min
+hr hour
+day 24 hr
+da day
+week 7 day
+year 365.24219879 day fuzz
+yr year
+month 1|12 year
+ms millisec
+us microsec
+
+/ Mass
+
+gram millikg
+gm gram
+mg milligram
+metricton kilokg
+
+/ Avoirdupois
+
+lb .45359237 kg
+pound lb
+lbf lb g
+ounce 1|16 lb
+oz ounce
+dram 1|16 oz
+dr dram
+grain 1|7000 lb
+gr grain
+shortton 2000 lb
+ton shortton
+longton 2240 lb
+
+/ Apothecary
+
+scruple 20 grain
+apdram 60 grain
+apounce 480 grain
+appound 5760 grain
+troypound appound
+
+/ Length
+
+meter m
+cm centimeter
+mm millimeter
+km kilometer
+nm nanometer
+micron micrometer
+angstrom decinanometer
+
+inch 2.54 cm
+in inch
+foot 12 in
+feet foot
+ft foot
+yard 3 ft
+yd yard
+rod 5.5 yd
+rd rod
+mile 5280 ft
+mi mile
+
+british 1200|3937 m/ft
+nmile 1852 m
+
+acre 4840 yd2
+
+cc cm3
+liter kilocc
+ml milliliter
+
+/ US Liquid
+
+gallon 231 in3
+imperial 1.20095
+gal gallon
+quart 1|4 gal
+qt quart
+pint 1|2 qt
+pt pint
+
+floz 1|16 pt
+fldr 1|8 floz
+
+/ US Dry
+
+dry 268.8025 in3/gallon fuzz
+peck 8 dry-quart
+pk peck
+bushel 4 peck
+bu bushel
+chaldron 36 bushel
+
+/ British
+
+brgallon 277.420 in3 fuzz
+brquart 1|4 brgallon
+brpint 1|2 brquart
+brfloz 1|20 brpint
+brpeck 554.84 in3 fuzz
+brbushel 4 brpeck
+
+/ Bottles
+
+bottle 750 milliliter
+/bottle fifth
+
+miniature 100 milliliter
+split 1|4 bottle
+half 1|2 bottle
+magnum 2 bottle
+jeroboam 4 bottle
+rehoboam 6 bottle
+methuselah 8 bottle
+salmanazar 12 bottle
+balthazar 16 bottle
+nebuchadnezzar 20 bottle
+sovereign 34 bottle
+
+/ Bottles - alternate names and spellings
+
+pony split
+fillette half
+tappithen 3 bottle
+rheoboam rehoboam
+shalmaneser salmanazar
+
+/ Energy Work
+
+newton kg-m/sec2
+nt newton
+N newton
+joule nt-m
+cal 4.1868 joule
+
+/ Electrical
+
+coulomb coul
+C coul
+ampere coul/sec
+amp ampere
+watt joule/sec
+volt watt/amp
+ohm volt/amp
+mho /ohm
+farad coul/volt
+henry sec2/farad
+weber volt-sec
+
+/ Light
+
+cd candela
+lumen cd sr
+lux cd sr/m2
+
+/ Wall Street Journal, July 2, 1993
+
+$ dollar
+argentinapeso $
+australiadollar .66 $
+bahraindinar 2.6522 $
+brazilcruzeiro .000019 $
+britainpound 1.49 $
+canadadollar .77 $
+czechkoruna .034 $
+chilepeso .0025 $
+chinarenminbi .174856 $
+colombiapeso .001495 $
+denmarkkrone .15 $
+ecuadorsucre .000539 $
+europeeuro 0.9142 $
+greatbritainpound britainpound
+hongkongdollar .13 $
+hungaryforint .011 $
+indiarupee .03211 $
+indonesiarupiah .0004782 $
+israelshekel .3642 $
+japanyen .0093 $
+jordandinar 1.4682 $
+kuwaitdinar 3.3173 $
+lebanonpound .000578 $
+malaysiaringgit .338 $
+maltalira 2.6042 $
+mexicopeso .3205128 $
+newzealanddollar .539 $
+norwaykrone .139 $
+pakistanrupee .037 $
+perunewsol .5065 $
+philippinespeso .03738 $
+polandzloty .000059 $
+saudiarabiariyal .26702 $
+singaporedollar .6157 $
+slovakkoruna .034 $
+southafricarand .21 $
+southkoreawon .001 $
+swedenkrona .13 $
+switzerlandfranc .66 $
+taiwandollar .038285 $
+thailandbaht .03962 $
+turkeylira .0000929 $
+unitedarabdirham .2723 $
+uruguaynewpeso .246852 $
+venezuelabolivar .011 $
+
+/ The following currencies are locked to the Euro:
+/ <URL:http://www.ecb.int/change/conversion.htm>
+belgiumfranc 1|40.3399 euro
+germanymark 1|1.95583 euro
+spainpeseta 1|166.386 euro
+francefranc 1|6.55957 euro
+irelandpunt 1|.787564 euro
+italylira 1|1936.27 euro
+luxembourgfranc 1|40.3399 euro
+netherlandsguilder 1|2.20371 euro
+austriaschilling 1|13.7603 euro
+portugalescudo 1|200.482 euro
+finlandmarkka 1|5.94573 euro
+greecedrachma 1|340.750 euro
+
+mark germanymark
+euro europeeuro
+bolivar venezuelabolivar
+peseta spainpeseta
+rand southafricarand
+escudo portugalescudo
+newsol perunewsol
+guilder netherlandsguilder
+hollandguilder netherlandsguilder
+peso mexicopeso
+yen japanyen
+lira italylira
+rupee indiarupee
+drachma greecedrachma
+franc francefranc
+markka finlandmarkka
+sucre ecuadorsucre
+poundsterling britainpound
+cruzeiro brazilcruzeiro
+
+/ computer
+
+baud bit/sec
+byte 8 bit
+block 512 byte
+kbyte 1024 byte
+megabyte 1024 kbyte
+gigabyte 1024 megabyte
+meg megabyte
+
+
+/ Trivia
+
+% 1|100
+admiraltyknot 6080 ft/hr
+apostilb cd/pi-m2
+are 1e+2 m2
+arpentcan 27.52 mi
+arpentlin 191.835 ft
+astronomicalunit au
+atmosphere 1.01325e+5 nt/m2
+atm atmosphere
+atomicmassunit 1.66044e-27 kg fuzz
+amu atomicmassunit
+bag 94 lb
+bakersdozen 13
+bar 1e+5 nt/m2
+barie 1e-1 nt/m2
+barleycorn 1|3 in
+barn 1e-28 m2
+barrel 42 gal
+barye 1e-1 nt/m2
+bev 1e+9 e-volt
+biot 10 amp
+blondel cd/pi-m2
+boardfoot 144 in3
+bolt 40 yd
+bottommeasure 1|40 in
+britishthermalunit 1.05506e+3 joule fuzz
+btu britishthermalunit
+refrigeration 12000 btu/ton-hour
+buck dollar
+Ci curie
+cable 720 ft
+caliber 1e-2 in
+calorie cal
+carat 205 mg
+caratgold 1|24
+cent centidollar
+cental 100 lb
+centesimalminute 1e-2 grade
+centesimalsecond 1e-4 grade
+century 100 year
+cfs ft3/sec
+chain 66 ft
+circularinch 1|4 pi-in2
+circularmil 1e-6|4 pi-in2
+clusec 1e-8 mm-hg m3/s
+coomb 4 bu
+cord 128 ft3
+cordfoot cord
+crith 9.06e-2 gm
+cubit 18 in
+cup 1|2 pt
+curie 3.7e+10 /sec
+dalton amu
+decade 10 yr
+diopter /m
+displacementton 35 ft3
+doppelzentner 100 kg
+dozen 12
+drop .03 cm3
+dyne cm-gm/sec2
+electronvolt e-volt
+ell 45 in
+engineerschain 100 ft
+engineerslink 100|100 ft
+equivalentfootcandle lumen/pi-ft2
+equivalentlux lumen/pi-m2
+equivalentphot cd/pi-cm2
+erg cm2-gm/sec2
+ev e-volt
+faraday 9.652e+4 coul
+fathom 6 ft
+fermi 1e-15 m
+fifth 4|5 qt
+fin 5 dollar
+finger 7|8 in
+firkin 9 gal
+footcandle lumen/ft2
+footlambert cd/pi-ft2
+fortnight 14 da
+franklin 3.33564e-10 coul
+frigorie kilocal
+furlong 220 yd
+Gy gray
+galileo 1e-2 m/sec2
+gamma 1e-9 weber/m2
+gauss 1e-4 weber/m2
+geodeticfoot british-ft
+geographicalmile 1852 m
+gilbert 7.95775e-1 amp
+gill 1|4 pt
+gray joule/kg
+gross 144
+gunterschain 22 yd
+hand 4 in
+hectare 1e+4 m2
+hefnercandle .92 cd
+hertz /sec
+Hz hertz
+hogshead 63 gallon
+hd hogshead
+homestead 1|4 mi2
+horsepower 550 ft-lb-g/sec
+hp horsepower
+hyl gm force sec2/m
+hz /sec
+imaginarycubicfoot 1.4 ft3
+karat 1|24
+kcal kilocal
+kcalorie kilocal
+kev 1e+3 e-volt
+key kg
+khz 1e+3 /sec
+kilderkin 18 gal
+knot nmile/hr
+lambert cd/pi-cm2
+langley cal/cm2
+last 80 bu
+league 3 mi
+lightyear c-yr
+line 1|12 in
+link 66|100 ft
+longhundredweight 112 lb
+longquarter 28 lb
+lusec 1e-6 mm-hg m3/s
+mach 331.46 m/sec
+marineleague 3 nmile
+maxwell 1e-8 weber
+metriccarat 200 mg
+mgd megagal/day
+mh millihenry
+mhz 1e+6 /sec
+mil 1e-3 in
+millennium 1000 year
+minersinch 1.5 ft3/min
+minim 1|60 fldr
+mo month
+mpg mile/gal
+mph mile/hr
+nail 1|16 yd
+nauticalmile nmile
+nit cd/m2
+noggin 1|8 qt
+nox 1e-3 lux
+ns nanosec
+oersted 2.5e+2 pi-amp/m
+oe oersted
+pace 36 in
+palm 3 in
+parasang 3.5 mi
+parsec au-radian/arcsec
+pascal nt/m2
+pc parsec
+pennyweight 1|20 oz
+pwt pennyweight
+percent %
+perch rd
+pf picofarad
+phot lumen/cm2
+pica 1|6 in
+pieze 1e+3 nt/m2
+pipe 4 barrel
+point 1|72 in
+poise gm/cm-sec
+pole rd
+poundal ft-lb/sec2
+pdl poundal
+proof 1|200
+psi lb-g/in2
+quarter 9 in
+quartersection 1|4 mi2
+quintal 100 kg
+quire 25
+R roentgen
+rackunit 1.75 in
+rad 100 erg/gm
+ream 500
+registerton 100 ft3
+rem 1e-2 sievert
+rhe 10 m2/nt-sec
+roentgen 2.58e-4 coulomb/kg
+rontgen roentgen
+rood 1.21e+3 yd
+rope 20 ft
+RU rackunit
+rutherford 1e+6 /sec
+rydberg 1.36054e+1 ev
+Sv sievert
+sabin 1 ft2
+sack 3 bu
+score 20
+seam 8 bu
+section mi2
+shed 1e-24 barn
+shippington 40 ft3
+shorthundredweight 100 lb
+shortquarter 25 lb
+siemens /ohm
+sievert joule/kg
+sigma microsec
+skein 120 yd
+skot 1e-3 apostilb
+slug lb-g-sec2/ft
+smoot 67 in
+span 9 in
+spat 4 pi sr
+spindle 14400 yd
+square 100 ft2
+stere m3
+sthene 1e+3 nt
+stilb cd/cm2
+stoke 1e-4 m2/sec
+stone 14 lb
+strike 2 bu
+surveyfoot british-ft
+surveyyard 3 surveyfoot
+surveyorschain 66 ft
+surveyorslink 66|100 ft
+tablespoon 4 fldr
+teaspoon 4|3 fldr
+tesla weber/m2
+therm 1e+5 btu
+thermie 1e+6 cal
+timberfoot ft3
+tnt 4.6e+6 m2/sec2
+tonne 1e+6 gm
+torr mm hg
+township 36 mi2
+tun 8 barrel
+U rackunit
+water gram g / cc
+wey 40 bu
+weymass 252 lb
+Xunit 1.00202e-13 m
+k 1.38047e-16 erg/degC
+
+
+degC K
+kelvin K
+brewster 1e-12 m2/newton
+degF 5|9 degC
+degreesrankine degF
+degrankine degreesrankine
+degreerankine degF
+degreaumur 10|8 degC
+drachm 60 grain
+poncelet 100 kg m g / sec
+denier .05|450 gram / m
+tex .001 gram / m
+englishell 45 inch
+scottishell 37.2 inch
+flemishell 27 inch
+planck 6.626e-34 joule-sec
+hbar 1.055e-34 joule-sec
+electronmass 9.1095e-31 kg
+protonmass 1.6726e-27 kg
+neutronmass 1.6606e-27 kg
+V volt
+eV e V
+bohrradius hbar2-C2/8.988e9 N m2-e2-electronmass
+becquerel 1|3.7e10 curie
+fresnel 1e12 hertz
+statcoul 1|2.99792458e9 coul
+statamp 1|2.99792458e9 amp
+statvolt 2.99792458e2 volt
+statcoulomb statcoul
+statampere statamp
+debye 3.336e-30 coul-m
+pulsatance 2 pi/sec
+rpm rev/minute
+rps rev/sec
+kilohm kiloohm
+megohm megaohm
+siderealyear 365.256360417 day
+siderealday 23.934469444 hour
+siderealhour 1|24 siderealday
+lunarmonth 29.5305555 day
+synodicmonth lunarmonth
+siderealmonth 27.32152777 day
+tropicalyear year
+solaryear year
+lunaryear 12 lunarmonth
+cran 37.5 brgallon
+kip 1000 lbf
+frenchfoot 16|15 ft
+frenchfeet frenchfoot
+toise 6 frenchfeet
+candle 1.02 candela
+militarypace 2.5 feet
+metre meter
+litre liter
+gramme gram
+iudiptheria 62.8 microgram
+iupenicillin .6 microgram
+iuinsulin 41.67 microgram
+cottonyarncount 2520 ft/pound
+linenyarncount 900 ft/pound
+worstedyarncount 1680 ft/pound
+metricyarncount meter/gram
+jewlerspoint 2 milligram
+