Explain pls :)

[L0cutus]

Hello!

 //Average samples
  if (msTotal > 0 && samples > 0)
  {
    windSpeed = 1.49 * 1000 / (msTotal / samples);
  }

Can you explain the expression: 1.49 * 1000 / (msTotal / samples) ?

#ifdef METRIC
  windSpeed =  windSpeed * 1.60934;
#endif
  MonPrintf("WindSpeed: %f\n", windSpeed);
  windSpeed = int((windSpeed + .05) * 10) / 10;

and also: int((windSpeed + .05) * 10) / 10;

Thanks!

[jhughes1010]

Let's start with the second question first as that calculation is more easy to explain. I'm rounding to the nearest 10th on windSpeed. Adding 5/100ths to the number takes care of the possible round up. Multiply by by 10, retrieve the truncated integer, then divide by 10 to get back to the original number.

I'll break down the other with attachment on UOM analysis. I need to refresh on this.

[jhughes1010]

Here's the UOM analysis after the average ms/samples is calculated.

[L0cutus]

1.49 was for miles per hour?

[jhughes1010]

Yes, 1.49 , was derived. Datasheet gives 2.4kph, subsequent multiply my 1.609 (if metric) gets us back to the 2.4kph.

[L0cutus]

1.49 was for miles per hour?

Yes, 1.49 , was derived. Datasheet gives 2.4kph, subsequent multiply my 1.609 (if metric) gets us back to the 2.4kph.

many thanks for reply, I'm also trying to build/program my weather station using PlatformIO and i have tried to build a multifile project like your project but wasn't so simple since I'm not a C/C++ developer at all :-)

[jhughes1010]

Good luck with your efforts!