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Formula with sine and degrees

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pitive35 Posted messages 81 Status Member -  
 jcm -
Bonjour, je dois faire une formule sur Excel avec des sinus, cosinus et des degrés, mais je n'y arrive pas,
Voici ma formule mathématique :
sin(HS)=sin(ϕ)×sin(δ)+cos(ϕ)×cos(δ)× cos(α)
ϕ : Latitude en degrés, dans mon tableau cellule EF2, par exemple 46°12'
δ : Déclinaison terrestre en degrés, cellule B6, par exemple -20.7°
α : angle solaire en degrés cellule D5, par exemple -120°

Dans mon exemple le résultat doit être -35°
Merci de votre aide.

3 answers

  1.
    via55 Posted messages 14393 Registration date   Status Member Last intervention   2 759
     
    Good evening

    The Sin and Cos functions in Excel use radians as the unit of calculation

    So, you need to convert the data to degrees using the RADIANS function

    For example

    SIN(RADIANS(50)) to get the sine of an angle of 50°

    Best regards
    20
    1. pitive35 Posted messages 81 Status Member 1
       
      Hello,
      Thank you, I have tried, but with my example it doesn't work.
      0
    2. jcm
       
      Thank you, it works....... perfect
      very good advice
      0
  2. Raymond PENTIER Posted messages 58213 Registration date   Status Contributor Last intervention   17 482
     
    Congratulations, pitive35!

    You have broken all records: the same character ""?"" means both
    Latitude, Terrestrial Declination, Solar Angle
    and we have to deal with it!

    ... just like we have to guess the difference between sin?(HS) and sin?(?) ...

    Retirement is great! Especially in the Caribbean ... :-)
    ☻ Raymond ♂
    3
    1. pitive35 Posted messages 81 Status Member 1
       
      Hello,

      I'm sorry my symbols didn't integrate, here is my formula:
      sin(HS) = sin(phi) x sin(theta) + cos(phi) x cos(theta) x cos(omega)
      phi: Latitude
      theta: declination
      omega: solar angle

      Thank you for letting me know, I hadn't noticed about my symbols.
      0
  3. Raymond PENTIER Posted messages 58213 Registration date   Status Contributor Last intervention   17 482
     
    Hello pitive35.

    Indeed, it's not quite the same ...
    First, you need to write the angles in degrees with decimals, without any symbols; so
    46°12' should be written as 46.2 ......... in D2, and RAD(D2) = 0.8063421 in E2
    -20°7' should be written as -20.1167 ... in D3, and RAD(D3) = -0.351108 in E3
    -120° remains written as -120 ............. in D4, and RAD(D4) = -2.094395 in E4

    Your formula will simply be written in E5:
    =SIN(E2)*SIN(E3)+COS(E2)*COS(E3)*COS(E4)
    which equals -0.57319953, and the angle whose sine has this value is
    =ASIN(E5) which gives -0.6104052 rad in E6
    or =DEGREES(E6) which displays -34.9736416 degrees in E7.

    File in xlsx: https://www.cjoint.com/c/CDig342d8ZD
    File in xls: https://www.cjoint.com/?CDig5encENf

    Best regards.
    --
    Retirement is great! Especially in the Caribbean ... :-)
    ☻ Raymond ♂
    1
    1. pitive35 Posted messages 81 Status Member 1
       
      Hello Raymond,
      Thank you very much, it's exactly the desired results.
      0