| 18 |
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| 19 |
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| 20 |
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int |
| 21 |
< |
jdate(month, day) /* Julian date (days into year) */ |
| 22 |
< |
int month, day; |
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> |
jdate( /* Julian date (days into year) */ |
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> |
int month, |
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> |
int day |
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> |
) |
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{ |
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static short mo_da[12] = {0,31,59,90,120,151,181,212,243,273,304,334}; |
| 27 |
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| 30 |
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| 32 |
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double |
| 33 |
< |
stadj(jd) /* solar time adjustment from Julian date */ |
| 34 |
< |
int jd; |
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> |
stadj( /* solar time adjustment from Julian date */ |
| 34 |
> |
int jd |
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> |
) |
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{ |
| 37 |
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return( 0.170 * sin( (4*PI/373) * (jd - 80) ) - |
| 38 |
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0.129 * sin( (2*PI/355) * (jd - 8) ) + |
| 41 |
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| 42 |
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| 43 |
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double |
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< |
sdec(jd) /* solar declination angle from Julian date */ |
| 45 |
< |
int jd; |
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> |
sdec( /* solar declination angle from Julian date */ |
| 45 |
> |
int jd |
| 46 |
> |
) |
| 47 |
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{ |
| 48 |
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return( 0.4093 * sin( (2*PI/368) * (jd - 81) ) ); |
| 49 |
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} |
| 50 |
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double |
| 53 |
< |
salt(sd, st) /* solar altitude from solar declination and solar time */ |
| 54 |
< |
double sd, st; |
| 53 |
> |
salt( /* solar altitude from solar declination and solar time */ |
| 54 |
> |
double sd, |
| 55 |
> |
double st |
| 56 |
> |
) |
| 57 |
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{ |
| 58 |
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return( asin( sin(s_latitude) * sin(sd) - |
| 59 |
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cos(s_latitude) * cos(sd) * cos(st*(PI/12)) ) ); |
| 61 |
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| 62 |
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| 63 |
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double |
| 64 |
< |
sazi(sd, st) /* solar azimuth from solar declination and solar time */ |
| 65 |
< |
double sd, st; |
| 64 |
> |
sazi( /* solar azimuth from solar declination and solar time */ |
| 65 |
> |
double sd, |
| 66 |
> |
double st |
| 67 |
> |
) |
| 68 |
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{ |
| 69 |
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return( -atan2( cos(sd)*sin(st*(PI/12)), |
| 70 |
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-cos(s_latitude)*sin(sd) - |
