Surrounded palaces

Why a palace is never read alone, which four palaces make up the surrounded set, and how to get them in each of the three programming languages.

For: everyone. Code and the predicate table are at the end of the page

Why it exists

Reading a palace on its own loses half the information. The convention in Zi Wei Dou Shu is that any palace is read together with its opposite palace and its two trine palaces. Those four together are the surrounded palaces (三方四正).

The most immediate reason is the empty palace — when a palace holds no major star, tradition says to "borrow the stars of the opposite palace". Even when it is not empty, malefics and mutagens anywhere in the surrounded set bear on the reading of the palace at the centre.

Which four palaces

Taking the palace in question as the reference slot, the other three are at fixed offsets:

Member	Slot	Notes
Target	`i`	The palace being read
Opposite	`i + 6`	Directly across; the most direct influence
Career position	`i + 4`	One of the two trines
Wealth position	`i + 8`	One of the two trines

Slots are taken modulo 12. On the chart these four positions form a triangle plus a diagonal: 三方 ("three directions") is the trine of three palaces, 四正 ("four squared") is those plus the opposite, four in all.

        i+4 (career position)
         ／      ＼
        ／        ＼
      i ──────── i+6 (opposite)
        ＼        ／
         ＼      ／
        i+8 (wealth position)

"Career position" and "wealth position" are names relative to the target palace, not the Career and Wealth palaces on the chart. They coincide only when the target is the Soul palace; for any other target, only the positional relationship is the same.

In code

All three programming languages accept either a palace index or a palace name:

let sp = astrolabe.surrounded_palaces(Palace::Soul).unwrap();
println!("{:?}", sp.opposite.name);

The four members are target, opposite, career (the career position) and wealth (the wealth position). On the chart used throughout these pages, taking the Soul palace as the target, they resolve to soul, surface, career and wealth.

Predicates

The surrounded-palace predicates share names with the single-palace ones, but check the union of the four palaces. They are identical across the three programming languages:

Method	Does
`have(stars)`	Do the four palaces together hold all the given stars
`have_one_of(stars)`	Do they hold any one of them
`not_have(stars)`	Do they hold none of them
`have_mutagen(m)`	Does any of the four carry the given mutagen
`not_have_mutagen(m)`	Do none of the four carry it

sp := chart.SurroundedPalaces(iztro.PalaceSoul)

sp.Have(iztro.StarTianfuMaj)                              // Tianfu in the surrounded set
sp.HaveOneOf(iztro.StarQingyangMin, iztro.StarTuoluoMin)  // Qingyang or Tuoluo in sight
sp.NotHaveMutagen(iztro.MutagenJi)                        // no Hua Ji in sight

The astrolabe also offers three shortcuts that skip fetching the surrounded set first:

chart.is_surrounded(PalaceName.SOUL, [MajorStar.TIANFU])
chart.is_surrounded_one_of(PalaceName.SOUL, [MinorStar.QINGYANG, MinorStar.TUOLUO])
chart.not_surrounded(PalaceName.SOUL, [MinorStar.HUOXING])

Don't confuse have with have_one_of

have requires every star in the list to be present; have_one_of requires only one. A question like "is a malefic in sight?" almost always wants have_one_of.

A worked example

Testing whether the Soul palace is "flanked by auspicious stars and clear of malefics":

from x_iztro.enums import PalaceName, MinorStar

chart = Astro().by_solar("2000-8-16", 2, "female", language="en-US")
sp = chart.surrounded_palaces(PalaceName.SOUL)

lucky = sp.have_one_of([MinorStar.ZUOFU, MinorStar.YOUBI,
                        MinorStar.WENCHANG, MinorStar.WENQU])
clean = sp.not_have([MinorStar.QINGYANG, MinorStar.TUOLUO,
                     MinorStar.HUOXING, MinorStar.LINGXING])

print(lucky, clean, lucky and clean)

True False False

This chart has Wenchang and Wenqu in the surrounded set, but it also sees some of Qingyang, Tuoluo, Huoxing and Lingxing, so the pattern does not hold.

Star classes and keys are on Stars.