Angle Classes and Converstions¶

GeodePy has 5 main angle classes to represent angles in different formats. These will be explored here along with how to convert between these types.

The 5 classes are:

Degrees, Minutes and Second (dms)
Degrees and Decimal Minutes (ddm)
Decimal Degrees (dec)
HP notation (hpa)
Gradians (gona)

Classes¶

Degrees, Minutes and Seconds (dms)¶

Angles expressed in degrees, minutes, and seconds.

Format: ddd° mm' ss.s"
Conversion: 1° = 60′, 1′ = 60″
Example: 123° 34' 56.2"

To initalise a dms class:

angle1 = geodepy.angles.DMSAngle(d, m, s)

Degrees and Decimal Minutes (ddm)¶

Angles expressed in degrees and minutes, with minutes shown as a decimal fraction.

Format: ddd° mm.mm'
Example: 123° 34.933'

To initalise a ddm class:

angle1 = geodepy.angles.DDMAngle(d, dm)

Decimal Degrees (dec)¶

Angles expressed entirely in decimal degrees.

Format: ddd.ddd°
Example: 123.5823°

To initalise a dec class:

angle1 = geodepy.angles.DECAngle(d)

HP Notation (hpa)¶

HP notation expresses latitude and longitude as positive values with hemisphere indicators.

Format: ddd.mmssss
Example: 123.231524°

To initalise a hpa class:

angle1 = geodepy.angles.HPAngle(hp)

Gradians (gona)¶

A metric-based angle unit where a full circle equals 400 gradians.

Format ggg.ggg
Conversion: 1 grad = 0.9°
Example: 137.5

To initalise a gona class:

angle1 = geodepy.angles.GONAngle(gon)

Using Angle Classes¶

Angle classes can be used to hold angle variables, transform to different angle types and complete arthimitc. These will be explored below.

First import GeodePy.

import geodepy.angles as angles

In this example a DMS angle will be created. This object can be initalised by including the degrees, minutes and seconds as arguments.

angle1 = angles.DMSAngle(30, 5, 42)
print(angle1)

>>30 5 42

Using this class we can get individual variables for degree minute and seconds componets seperately.

print(angle1.degree)
print(angle1.minute)
print(angle1.second)

>>30
>>5
>>42

The methods within the class can also be used to convert the angle into different types.

print(angle1.ddm())
print(angle1.dec())
print(angle1.gona())
print(angle1.hpa())
print(angle1.rad())

>>30 5.7
>>30.095
>>33.4388888889
>>30.0542
>>0.5252568383876934

This can be completed with any of the 5 angle classes within GeodePy.

Arthimitc can be completed on angle classes as seen below. First a new angle needs to be defined. This will be done using the DDM Angle class

angle2 = angles.DDMAngle(40, 10.52)

Now this new anlge class can be added or subtracted from the first class

angle3 = angle1 + angle2
angle4 = angle2 - angle1

print(angle3)
print(type(angle3))
print(angle4)
print(type(angle4))

>>70 16 13.2
>><class 'geodepy.angles.DMSAngle'>
>>10 4.82
>><class 'geodepy.angles.DDMAngle'>

As can be seen here, simple math can be completed on these classes. It should be noted that the result will have the class of the first variable in the calculation.

Note

Operations can only be preformed when both angles are an object.

The following operators can be preformed on angle objects:

Operation	Method
Addition	‘+’
Subtraction	‘-’
Multiplication	‘*’
Division	‘/’
Equality	‘==’
Not Equal	‘!=’
Less Than	‘<’
Greater Than	‘>’
Modulo	‘%’
Round	round()

Caution

Basic arthimitc should not be completed on HPA class. These should be converted to decimal degree first.