Obyek Pengukuran

Modul django.contrib.gis.measure megandung obyek-obyek yang mengizinkan untuk gambaran nyaman dari jarak dan unit kawasan dari pengukuran. [1] Khususnya, itu menerapkan dua obyek, Distance dan Area -- kedua dari yang mungkin mengakses melalui nama lain kenyamanan D dan A, masing-masing.

Contoh

Distance objects may be instantiated using a keyword argument indicating the context of the units. In the example below, two different distance objects are instantiated in units of kilometers (km) and miles (mi):

>>> from django.contrib.gis.measure import D, Distance
>>> d1 = Distance(km=5)
>>> print(d1)
5.0 km
>>> d2 = D(mi=5)  # `D` is an alias for `Distance`
>>> print(d2)
5.0 mi

For conversions, access the preferred unit attribute to get a converted distance quantity:

>>> print(d1.mi)  # Converting 5 kilometers to miles
3.10685596119
>>> print(d2.km)  # Converting 5 miles to kilometers
8.04672

Moreover, arithmetic operations may be performed between the distance objects:

>>> print(d1 + d2)  # Adding 5 miles to 5 kilometers
13.04672 km
>>> print(d2 - d1)  # Subtracting 5 kilometers from 5 miles
1.89314403881 mi

Two Distance objects multiplied together will yield an Area object, which uses squared units of measure:

>>> a = d1 * d2  # Returns an Area object.
>>> print(a)
40.2336 sq_km

To determine what the attribute abbreviation of a unit is, the unit_attname class method may be used:

>>> print(Distance.unit_attname("US Survey Foot"))
survey_ft
>>> print(Distance.unit_attname("centimeter"))
cm

Satuan Didukung

Satuan Atribut	Nama penuh atau nama lain
km	Kilometer
mi	Mil
m	Meter
yd	Yard
ft	Kaki (Internasional)
survey_ft	Kaki Amerika Serikat, penelitian kaki Amerika Serikat
inci	Inci
cm	Sentimeter
mm	Milimeter
um	Mikrometer
british_ft	Kaki Inggris (Sears 1922)
british_yd	Yard Inggris (Sears 1922)
british_chain_sears	British chain (Sears 1922)
indian_yd	Yard India, Yard (India)
sears_yd	Yard (Sears)
clarke_ft	Kaki Clarke
chain	Chain
chain_benoit	Chain (Benoit)
chain_sears	Chain (Sears)
british_chain_benoit	British chain (Benoit 1895 B)
british_chain_sears_truncated	British chain (Sears 1922 truncated)
gold_coast_ft	Gold Coast foot
link	Tautan
link_benoit	Link (Benoit)
link_sears	Link (Sears)
clarke_link	Tautan Clarke
fathom	Fathom
rod	Rod
furlong	Furlong, Furrow Long
nm	Nautical Mile
nm_uk	Nautical Mile (UK)
german_m	German legal metre

Catatan

Atribut-atribut Area adalah sama seperti atribut-atribut Distance, kecuali mereka diawali dengan sq_ (satuan kawasan adalah persegi di alam). Sebagai contoh, Area(sq_m=2) membuat sebuah obyek Area mewakili dia meter persegi.

API pengukuran

Distance

class Distance(**kwargs)[sumber]

To initialize a distance object, pass in a keyword corresponding to the desired unit attribute name set with desired value. For example, the following creates a distance object representing 5 miles:

>>> dist = Distance(mi=5)

__getattr__(unit_att)

Returns the distance value in units corresponding to the given unit attribute. For example:

>>> print(dist.km)
8.04672

classmethod unit_attname(unit_name)

Returns the distance unit attribute name for the given full unit name. For example:

>>> Distance.unit_attname("Mile")
'mi'

class D

Nama lain untuk kelas Distance.

Area

class Area(**kwargs)[sumber]

To initialize an area object, pass in a keyword corresponding to the desired unit attribute name set with desired value. For example, the following creates an area object representing 5 square miles:

>>> a = Area(sq_mi=5)

__getattr__(unit_att)

Returns the area value in units corresponding to the given unit attribute. For example:

>>> print(a.sq_km)
12.949940551680001

classmethod unit_attname(unit_name)

Returns the area unit attribute name for the given full unit name. For example:

>>> Area.unit_attname("Kilometer")
'sq_km'

class A

Nama lain untuk kelas Area.

Catatan kaki

[1]	Robert Coup adalah penulis awal dari ukuran obyek-obyek, dan terinspirasi oleh pekerjaan Brian Beck dalam geopy dan pekerjaan PhD Geoff Biggs pada dimensi satuan untuk robotik.