dockapps/wmweather+/convert.c

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#include "config.h"
/* Copyright (C) 2002 Brad Jorsch <anomie@users.sourceforge.net>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <math.h>
#if TM_IN_SYS_TIME
# if TIME_WITH_SYS_TIME
# include <sys/time.h>
# include <time.h>
# else
# if HAVE_SYS_TIME_H
# include <sys/time.h>
# else
# include <time.h>
# endif
# endif
#else
#include <time.h>
#endif
#include <ctype.h>
#include <string.h>
#include <stdlib.h>
#include "convert.h"
/*
* To indicate unavailable data
* 999 is used for temperature
* x<0 is used for rh, pressure, and windspeed
*/
/* Calculations */
int rh_C(int temp_C, int dewpt_C){
float f;
if(temp_C==999 || dewpt_C==999) return 999;
f=1782.75*(dewpt_C-temp_C)/((237.7+dewpt_C)*(237.7+temp_C));
return round(pow(10, f+2));
}
int rh_F(int temp_F, int dewpt_F){
float f;
if(temp_F==999 || dewpt_F==999) return 999;
f=3208.95*(dewpt_F-temp_F)/((395.86+dewpt_F)*(395.86+temp_F));
return round(pow(10, f+2));
}
int heatindex_C(int temp_C, int rh){
#if 1
if(temp_C==999 || temp_C<21 || rh<0) return 999;
return heatindex_F(temp_C2F(temp_C), rh);
#else
int temp2, rh2;
if(temp_C==999 || temp_C<38 || rh<0) return 999;
temp2=temp_C*temp_C;
rh2=rh*rh;
return round(16.18754948 + 2.900509394*temp_C - 0.0221545692*temp2 + 4.20938791*rh - 0.26300889*temp_C*rh + 0.0039811176*temp2*rh - 0.02956469*rh2 + 0.001305828*temp_C*rh2 - 6.4476e-06*temp2*rh2);
#endif
}
int heatindex_F(int temp_F, int rh){
int temp2, temp3, rh2, rh3;
if(temp_F==999 || temp_F<70 || rh<0) return 999;
temp2=temp_F*temp_F;
temp3=temp2*temp_F;
rh2=rh*rh;
rh3=rh2*rh;
return round(16.923 + .185212*temp_F + 5.37941*rh - .100254*temp_F*rh + (9.41695e-3)*temp2 + (7.28898e-3)*rh2 + (3.45372e-4)*temp2*rh - (8.14971e-4)*temp_F*rh2 + (1.02102e-5)*temp2*rh2 - (3.8646e-5)*temp3 + (2.91583e-5)*rh3 + (1.42721e-6)*temp3*rh + (1.97483e-7)*temp_F*rh3 - (2.18429e-8)*temp3*rh2 + (8.43296e-10)*temp2*rh3 - (4.81975e-11)*temp3*rh3);
#if 0
return round(-42.379 + 2.04901523*temp_F + 10.14333127*rh - 0.22475541*temp_F*rh - .00683783*temp2 - .05481717*rh2 + .00122874*temp2*rh + .00085282*temp_F*rh2 - .00000199*temp2*rh2);
#endif
}
int windchill_C(int temp_C, int windspeed){
if(temp_C==999 || windspeed<0) return 999;
return windchill_F(temp_C2F(temp_C), windspeed);
}
int windchill_F(int temp_F, int windspeed){
double ret;
if(temp_F==999 || windspeed<0) return 999;
ret=35.74 + 0.6215*temp_F + (-35.75 + 0.4275*temp_F)*pow(windspeed*50292/57875.0, 0.16);
if(ret>temp_F) return temp_F;
return round(ret);
}
/* Length Conversions */
int in2cm(int in){
if(in<0) return in;
return round(in*2.54);
}
float m2mi(int meters){
if(meters<0) return meters;
return meters*125/201168;
}
/* Windspeed Conversions */
int knots2mph(int knots){
if(knots<0) return knots;
return round(knots*57875/50292.0);
}
int knots2kph(int knots){
if(knots<0) return knots;
return round(knots*463/250.0);
}
int kph2knots(int kph){
if(kph<0) return kph;
return round(kph*250/463.0);
}
int knots2mps(int knots){
if(knots<0) return knots;
return round(knots*463/900.0);
}
int mps2knots(int mps){
if(mps<0) return mps;
return round(mps*900/463.0);
}
int knots2beaufort(int knots){
if(knots<0) return knots;
if(knots<1) return 0;
if(knots<=3) return 1;
if(knots<=6) return 2;
if(knots<=10) return 3;
if(knots<=16) return 4;
if(knots<=21) return 5;
if(knots<=27) return 6;
if(knots<=33) return 7;
if(knots<=40) return 8;
if(knots<=47) return 9;
if(knots<=55) return 10;
if(knots<=63) return 11;
return 12;
}
/* Temperature Conversions */
int temp_C2F(int temp_C){
if(temp_C==999) return 999;
return round(temp_C*9/5.0+32);
}
int temp_F2C(int temp_F){
if(temp_F==999) return 999;
return round((temp_F-32)*5/9.0);
}
/* Pressure Conversions */
float inHg2mmHg(float inHg){
if(inHg<0) return inHg;
return inHg*25.4;
}
float inHg2hPa(float inHg){
if(inHg<0) return inHg;
return inHg*33.8639;
}
float inHg2atm(float inHg){
if(inHg<0) return inHg;
return inHg*.033421052632;
}
float hPa2inHg(float hPa){
if(hPa<0) return hPa;
return hPa/33.8639;
}
/* Time Conversions */
/* NOTE: y%400==100 because y=year-1900 */
#define is_leap(y) (y%4==0 && (y%100!=0 || y%400==100))
/* mktime for UTC, more or less.
* Differences:
* - no range checking
* - never recalculates tm_wday or tm_yday
*/
time_t mkgmtime(struct tm *tm){
static long msec[]={0, 2678400, 5097600, 7776000, 10368000, 13046400, 15638400, 18316800, 20995200, 23587200, 26265600, 28857600};
time_t t;
int i;
t=0;
if(tm->tm_year>70){
for(i=70; i<tm->tm_year; i++){
t+=31536000;
if(is_leap(i)) t+=86400;
}
} else if(tm->tm_year<70){
for(i=69; i>=tm->tm_year; i--){
t-=31536000;
if(is_leap(i)) t-=86400;
}
}
t+=msec[tm->tm_mon];
if(tm->tm_mon>1 && is_leap(tm->tm_year)) t+=86400;
t+=(((tm->tm_mday-1)*24+tm->tm_hour)*60+tm->tm_min)*60+tm->tm_sec;
return t;
}
int utc2local(int hm, int *month, int *day, int *year, int *wday){
time_t t=time(NULL);
struct tm *tm;
tm=gmtime(&t);
tm->tm_hour=hm/100;
tm->tm_min=hm%100;
if(month!=NULL && *month!=-1) tm->tm_mon=*month-1;
if(day!=NULL && *day!=-1) tm->tm_mday=*day;
if(year!=NULL && *year!=-1) tm->tm_year=*year;
t=mkgmtime(tm);
tm=localtime(&t);
if(month!=NULL) *month=tm->tm_mon+1;
if(day!=NULL) *day=tm->tm_mday;
if(year!=NULL) *year=tm->tm_year;
if(wday!=NULL) *wday=tm->tm_wday;
return tm->tm_hour*100+tm->tm_min;
}
int local2utc(int hm, int *month, int *day, int *year, int *wday){
time_t t=time(NULL);
struct tm *tm;
tm=localtime(&t);
tm->tm_hour=hm/100;
tm->tm_min=hm%100;
if(month!=NULL && *month!=-1) tm->tm_mon=*month-1;
if(day!=NULL && *day!=-1) tm->tm_mday=*day;
if(year!=NULL && *year!=-1) tm->tm_year=*year;
t=mktime(tm);
tm=gmtime(&t);
if(month!=NULL) *month=tm->tm_mon+1;
if(day!=NULL) *day=tm->tm_mday;
if(year!=NULL) *year=tm->tm_year;
if(wday!=NULL) *wday=tm->tm_wday;
return tm->tm_hour*100+tm->tm_min;
}
void fix_date(int *month, int *day, int *year, int *wday){
time_t t=time(NULL);
struct tm *tm;
tm=gmtime(&t);
if(month!=NULL && *month!=-1) tm->tm_mon=*month-1;
if(day!=NULL && *day!=-1) tm->tm_mday=*day;
if(year!=NULL && *year!=-1) tm->tm_year=*year;
t=mkgmtime(tm);
tm=gmtime(&t);
if(month!=NULL) *month=tm->tm_mon+1;
if(day!=NULL) *day=tm->tm_mday;
if(year!=NULL) *year=tm->tm_year;
if(wday!=NULL) *wday=tm->tm_wday;
}
int hm2min(int hm){
return hm/100*60+hm%100;
}
/* Letter Case (destructive!) */
char *str_upper(char *str){
char *c;
for(c=str; *c!='\0'; c++){
*c=toupper(*c);
}
return str;
}
char *str_lower(char *str){
char *c;
for(c=str; *c!='\0'; c++){
*c=tolower(*c);
}
return str;
}
/* Angle conversions */
/* Convert radian angle to degrees */
double rad2deg(double angle) {
return 180.0*angle/PI;
}
/* Convert degree angle to radians */
double deg2rad(double angle) {
return PI*angle/180.0;
}
/* Date conversions */
/* Numerical day-of-year from month, day and year */
int mdy2doy(int mn, int dy, int y) {
return 275*mn/9 - ((y%4==0 && (y%100!=0 || y%400==100))?1:2)*(mn + 9)/12 + dy-30;
}
/* Julian day from month/day/year */
double mdy2jd(int year, int month, int day) {
int A, B;
year+=1900;
if (month <= 2) {
year -= 1;
month += 12;
}
A=year/100;
B=2 - A + A/4;
return (int)(365.25*(year + 4716)) + (int)(30.6001*(month+1)) + day + B - 1524.5;
}
/* convert Julian Day to centuries since J2000.0. */
double jd2jcent(double jd) {
return (jd - 2451545.0)/36525.0;
}
/* convert centuries since J2000.0 to Julian Day. */
double jcent2jd(double t) {
return t * 36525.0 + 2451545.0;
}
/* Lat/Long conversions */
static double parse_dd_or_dms(char *s, char **e){
double deg;
*e=s;
if(strchr(s, 'x') || strchr(s, 'X')) return NAN;
if(!strchr(s, '\'')){
if(!isdigit(*s) && *s!='.') return NAN;
return strtod(s, e);
}
if(!isdigit(*s)) return NAN;
deg=strtol(s, e, 10);
if(*e==s || *e==NULL || **e!='\'') return deg;
s=++(*e);
if(!isdigit(*s)) return deg;
deg+=strtol(s, e, 10)/60.0;
if(*e==s || *e==NULL || **e!='\'') return deg;
s=++(*e);
if(!isdigit(*s) && *s!='.') return NAN;
deg+=strtod(s, e)/3600.0;
if(*e!=s && *e!=NULL && **e=='\'') (*e)++;
return deg;
}
int str2dd(char *s, double *lat, double *lon){
char *e;
int dir=0;
char c;
c=toupper(*s);
if(c=='+' || c=='N'){
s++; dir=1;
}
if(c=='-' || c=='S'){
s++; dir=-1;
}
*lat=parse_dd_or_dms(s, &e);
if(isnan(*lat) || e==NULL || e==s || *e=='\0') return 0;
if(!dir){
c=toupper(*e);
if(c=='N') dir=1;
if(c=='S') dir=-1;
if(dir) e++;
}
if(dir<0) *lat=-*lat;
while(isspace(*e)) e++;
if(*e=='\0') return 0;
s=e; dir=0;
c=toupper(*s);
if(c=='+' || c=='W'){
s++; dir=1;
}
if(c=='-' || c=='E'){
s++; dir=-1;
}
*lon=parse_dd_or_dms(s, &e);
if(isnan(*lon) || e==s) return 0;
if(e==NULL || *e=='\0') return 1;
if(dir==0){
c=toupper(*e);
if(c=='W') dir=1;
if(c=='E') dir=-1;
if(dir!=0) e++;
}
if(dir<0) *lon=-*lon;
return (*e=='\0');
}