time_t

[XosRod]

hello.
I have a little problem:
all the examples where "time_t" appears give the following error:

/home/xose/PROXECTOS/SeguidorSolar/SolarCalculator-main(!!)/examples/SolarCalculatorTimeLib/SolarCalculatorTimeLib.ino:68:1: error: 'time_t' does not name a type; did you mean 'size_t'?
time_t toUtc(time_t local)
^~~~~~
size_t
/home/xose/PROXECTOS/SeguidorSolar/SolarCalculator-main(!!)/examples/SolarCalculatorTimeLib/SolarCalculatorTimeLib.ino:79:1: error: 'time_t' does not name a type; did you mean 'size_t'?
time_t compileTime()
^~~~~~
size_t
/home/xose/PROXECTOS/SeguidorSolar/SolarCalculator-main(!!)/examples/SolarCalculatorTimeLib/SolarCalculatorTimeLib.ino: In function 'void setup()':
/home/xose/PROXECTOS/SeguidorSolar/SolarCalculator-main(!!)/examples/SolarCalculatorTimeLib/SolarCalculatorTimeLib.ino:27:17: error: 'compileTime' was not declared in this scope
setTime(toUtc(compileTime()));
^~~~~~~~~~~
/home/xose/PROXECTOS/SeguidorSolar/SolarCalculator-main(!!)/examples/SolarCalculatorTimeLib/SolarCalculatorTimeLib.ino:27:11: error: 'toUtc' was not declared in this scope
setTime(toUtc(compileTime()));
^~~~~
/home/xose/PROXECTOS/SeguidorSolar/SolarCalculator-main(!!)/examples/SolarCalculatorTimeLib/SolarCalculatorTimeLib.ino:27:3: error: 'setTime' was not declared in this scope
setTime(toUtc(compileTime()));
^~~~~~~
/home/xose/PROXECTOS/SeguidorSolar/SolarCalculator-main(!!)/examples/SolarCalculatorTimeLib/SolarCalculatorTimeLib.ino:33:3: error: 'time_t' was not declared in this scope
time_t utc = now();
^~~~~~
/home/xose/PROXECTOS/SeguidorSolar/SolarCalculator-main(!!)/examples/SolarCalculatorTimeLib/SolarCalculatorTimeLib.ino:33:3: note: suggested alternative: 'size_t'
time_t utc = now();
^~~~~~
size_t
/home/xose/PROXECTOS/SeguidorSolar/SolarCalculator-main(!!)/examples/SolarCalculatorTimeLib/SolarCalculatorTimeLib.ino:35:22: error: 'utc' was not declared in this scope
calcEquationOfTime(utc, eq);
^~~
/home/xose/PROXECTOS/SeguidorSolar/SolarCalculator-main(!!)/examples/SolarCalculatorTimeLib/SolarCalculatorTimeLib.ino:35:22: note: suggested alternative: 'putc'
calcEquationOfTime(utc, eq);
^~~
putc
/home/xose/PROXECTOS/SeguidorSolar/SolarCalculator-main(!!)/examples/SolarCalculatorTimeLib/SolarCalculatorTimeLib.ino: At global scope:
/home/xose/PROXECTOS/SeguidorSolar/SolarCalculator-main(!!)/examples/SolarCalculatorTimeLib/SolarCalculatorTimeLib.ino:68:1: error: 'time_t' does not name a type; did you mean 'size_t'?
time_t toUtc(time_t local)
^~~~~~
size_t
/home/xose/PROXECTOS/SeguidorSolar/SolarCalculator-main(!!)/examples/SolarCalculatorTimeLib/SolarCalculatorTimeLib.ino:79:1: error: 'time_t' does not name a type; did you mean 'size_t'?
time_t compileTime()
^~~~~~
size_t

exit status 1

Compilation error: 'time_t' does not name a type; did you mean 'size_t'?

how could i solve it?

[jpb10]

For this particular example, make sure that the Time library is installed.

[XosRod]

hello, thank you for replying.
I have installed the TimeLib-2.1.0 library.
is it valid?

[XosRod]

sorry.
I have switched to the time library and the sketch already compiles.
thanks

[XosRod]

I have tested the library as it comes and it works fine, but if I change the date and time to manual and enter the data myself the azimuth and altitude results are very very wrong with respect to the NOAA ones (about 30º).
I don't understand

[jpb10]

Please post your code, input values and program output.

Some common sources of error:

• Input time not in UTC
• Wrong sign for longitude
• Not adding the UTC offset to the sunrise and sunset times

[XosRod]

CODIGO:#include <SolarCalculator.h>
#include <TimeLib.h>

// Location
double latitude = 42.1654743206;
double longitude = -8.5030256541;
int utc_offset = +2;

void setup()
{
Serial.begin(9600);

double transit, sunrise, sunset; // Event times, in hours (UTC)
double eq; // Equation of time, in minutes
double ra, dec, r; // Equatorial coordinates, in degrees and AUs
double az, el; // Horizontal coordinates, in degrees

// Set system time to compile time
//setTime(toUtc(compileTime()));

// Set time manually (hr, min, sec, day, mo, yr)
setTime(16, 00, 00, 15, 10, 2023);

// Get current time
time_t utc = now();

SALIDA:
Sunrise: 08:46
Transit: 14:20
Sunset: 19:53
Eq of time: 14.21 min
RA: 13.359h Dec: -8.58º R: 0.997200 AU
Az: 238.80º El: 18.69º

Salida NOAA
Az: 217.65º El: 31.58º

[XosRod]

if setTime(14,00,00,15,10,2023)
the output is:
Sunrise: 08:46
Transit: 14:20
Sunset; 19:53
Eq of time: 14.19 min
RA: 13.353h Dec: -8.55º R; 0.997224 AU
Az: 210.47º El: 34.37º

[XosRod]

the latter is quite consistent with the NOAA output.

[jpb10]

It should agree with NOAA within rounding error, or 0.01 degree.

[XosRod]

it is evident that the error was in not setting the setTime in UTC

[XosRod]

thank you for your work