I am looking for some technical help for a horary software that I am
In KP horary, we choose a random number and the value of ascendant is
derived on the basis of that number. We then need to calculate the
other houses with that ascendant in view. I need someone who can guide
me in calculating the placidus house systems with this fixed
ascendant, and using other data like latitude, etc.
If anyone of you great guys is willing to help, it'd be wonderful.
Even links to useful resources, and ideas will help.
Thank you in anticipation friends
> other houses with that ascendant in view. I need someone who can guide
> me in calculating the placidus house systems with this fixed
> ascendant, and using other data like latitude, etc.
Excerpts from Michael P. Munkasey's "An Astrological House Formulary"...
The following standard abbreviations are used in the mathematics which
e represents the obliquity of the ecliptic
f represents the terrestrial latitude
ASC is the ascendant
MC is the MC
RAMC is the Right Ascension of the MC
F, G, J, K, and L are working terms, unimportant astronomically
+. -, x (or, *), ÷, = represent their normal arithmetic functions
SIN, COS, TAN, COT, etc. represent the trigonometric functions
For calculator purposes: COT = (1 ÷ TAN ) and vice-versa, etc.
ARCSIN, ARCCOS, ARCTAN, etc. represent the trig inverses
H11, etc. stands for the offset to compute the cusp of house eleven, etc.
C11, etc. stands for the value of the cusp of house eleven, etc.
Standard computer notation parenthesis nesting conventions are used
throughout the formulations. That is, three left parenthesis must be
balanced by three right parenthesis. Calculations are always performed
within the inner parenthesis first, and then outward to the outer
parenthesis. Persons attempting the mathematics herein should refer to
reasonable reference books if they are unfamiliar with trigonometric
procedures. Particularly, the process of adjusting house cusp
calculations for the correct trigonometric quadrant can be somewhat
tricky if not performed with care. House cusps which are over 360° or
under 0° should be converted to lie between 0° and 360° . That is, if
you compute a house cusp as being 372° then this should be changed to 12
Aries. Add 360° to any negative values or results. House cusps with
values between 0° and 29.99° lie in Aries; between 30° and 59.99° in
Taurus; between 60° and 89.99° degrees in Gemini, and so forth around
the zodiac and through the signs.
PRELIMINARY CALCULATIONS AND THE PERSONAL SENSITIVE POINTS
1. The RAMC (the right ascension of the midheaven) is computed from
Local Sidereal Time (LST) by converting time units to degree units. An
example of this calculation follows:
Given an LST of 12H 15M 00S, then first convert this to a decimal form
of time, or 12.25 hours. 12.25 x 15 = 183.75° which is the RAMC.
Given an LST of 6H 27M 14S, then convert this to a decimal form of time,
or 6.453889 hours. 6.453889 x 15 = 96.808333°.
2. MC = ARCTAN ( TAN (RAMC) ÷ COS e )
3. ASC = ARCCOT (- ( (TAN f x SIN e) + (SIN RAMC x COS e) ) ÷ COS RAMC)
4. EQA = ARCCOT ( - ( TAN RAMC x COS e) )
5. VTX = ARCCOT (- ( (COT f x SIN e) - (SIN RAMC x COS e) ) ÷ COS RAMC)
6. CAS = ARCCOT (- ( (COT f x SIN e) + (SIN RAMC x COS e) ) ÷ COS RAMC)
7. PAS = ARCCOT ( ( (TAN f x SIN e) - (SIN RAMC x COS e) ) ÷ COS RAMC)
8. ARI The Aries Point is always zero of Aries.
9. The declination of any point on the ecliptic can be calculated from:
declination = ARCSIN ( SIN (zodiacal longitude of point ) x SIN e)
10. The obliquity of the ecliptic, for any date in modern times, is
e = 23o 27' 08.26" - 46.845" x T - .0059" x T2 + .00181" x T3
where T is in fractions of a century starting from Jan 1, 1900
THE PLACIDIAN HOUSE SYSTEM FORMULATION
1. Compute the RAMC, MC, and ASC in the normal manner. Use the MC as the
cusp of the tenth house and the ASC as the cusp of the first house. This
is a very fast converging algorithm adapted from a work by M.
2. Determine the following house cusp intervals:
H11 = RAMC + 30° H2 = RAMC + 120°
H12 = RAMC + 60° H3 = RAMC + 150°
3. Set the Semi-arc ratios:
F11 = 1 ÷ 3 F2 = 2 ÷ 3
F12 = 2 ÷ 3 F3 = 1 ÷ 3
4. Compute the cuspal declinations:
D11 = ARCSIN ( SIN e x SIN H11 ) D2 = ARCSIN ( SIN e x SIN H2 )
D12 = ARCSIN ( SIN e x SIN H12 ) D3 = ARCSIN ( SIN e x SIN H3 )
5. Compute the first intermediate values:
A11 = F11 x ( ARCSIN ( TAN f x TAN D11 ) )
A12 = F12 x ( ARCSIN ( TAN f x TAN D12 ) )
A2 = F2 x ( ARCSIN ( TAN f x TAN D2 ) )
A3 = F3 x ( ARCSIN ( TAN f x TAN D3) )
6. Compute the house cusp positions as follows:
M11 = ARCTAN ( SIN A11 ÷ ( COS H11 x TAN D11) )
M12 = ARCTAN ( SIN A12 ÷ ( COS H12 x TAN D12) )
M2 = ARCTAN ( SIN A2 ÷ ( COS H2 x TAN D2) )
M3 = ARCTAN ( SIN A3 ÷ ( COS H3 x TAN D3) )
7. Compute the intermediate house cusps:
R11 = ARCTAN ( ( TAN H11 x COS M11 ) ÷ COS ( M11 + e) )
R12 = ARCTAN ( ( TAN H12 x COS M12 ) ÷ COS ( M12 + e) )
R2 = ARCTAN ( ( TAN H2 x COS M2 ) ÷ COS ( M2 + e) )
R3 = ARCTAN ( ( TAN H3 x COS M3 ) ÷ COS ( M3 + e) )
8. Substitute: D11 = R11; D12 = R12; D2 = R2; and D3 = R3. Then repeat
steps 5 thru 8 again. Substitute the R's for the D's a third time and
repeat steps 5 thru 8. The answer for R on the third try is the cusp you
9. Compute the individual house cusps as follows:
C11 = R11 C5 = 180° + C11
C12 = R12 C6 = 180° + C12
C2 = R2 C8 = 180° + C2
C3 = R3 C9 = 180° + C3
End of excerpt...
Hope that helps. :)
Free Astrology Resources (FAR)
What I need to do is to relate the ascendant to this. Like for a given
Ascendant, I want to calculate teh position of the houses for a given
Hmm.. I think I want to create something similar to one of those table
of houses books that are available in the market.
Is there anything that can help me go forward?
The "real" ascendant is dependent on time & location. If you follow the
algorithm, you'll see that Cusp 10 (and thus Cusp 4 as well) are the
same regardless of latitude. The MC changes with longitude in the time
conversion step (because the time on our clocks is based on the
longitude) and the ascendant is "normally" based on the computed MC
(which means it's automatically corrected for longitude in that step as
Only Cusps 1 & 7 actually have anything to do with the ascendant and
they don't change with the latitude.
The other cusps are corrected for latitude in step 5.
(I'm not happy with my wording above, I hope it doesn't make things more
> Hmm.. I think I want to create something similar to one of those table
> of houses books that are available in the market.
I'm curious. Have you done any programming before?
Once you've calculated the house cusps, creating a table should be easy. :)
> Is there anything that can help me go forward?
Since you're deriving your ascendant from a random number, you aren't
using the true ascendant when you calculate your houses. I think this
would through off all your houses anyway, so why don't you just
substitute the formula you are using to derive the ascendant in for the
formula that I gave you and just calculate everything else as given?
The majority of the calculations depend on the MC, so I "think" that as
long as you don't change the MC, you "should" be ok...but I'm not sure.
(Except, I'm guessing, the cardinal and succedant houses might get
squished or stretched, since you are altering the relationship between
the Ascendant and the MC). Why not give it a try and find out?
Since you're using a false ascendant, instead of the real one you're not
going to get "real" Placidus Houses anyway, so why not call them Faux
Placidus or maybe Gupta Houses or something. :)
After re-thinking things a bit (and re-reading your original question)
I think what you want is as follows...
You have a given Asc and a known latitude/longitude.
1. Solve the Ascendant equation (Equation 3, in PRELIMINARY CALCULATIONS
AND THE PERSONAL SENSITIVE POINTS) for RAMC.
2. Plug the RAMC you just calculated into the equation for the MC and
find the corresponding MC.
3. Use the ASC, MC and RAMC that you now have to calculate all the other
cusps as per the algorithm I already gave you.
P.S. You're on your own with doing the trig needed to solve those first
two equations. :)
I solved the ascendant equation to derive the RAMC, and then I was
able to calculate the rest of the houses using the RAMC.
Yes, you are correct.
Thank you very much for your help.
You're welcome. I'm glad I was able to help.