TotalDepth.common.units¶

This provides Unit conversion information from lookup sources.

The primary source is Schlumberger’s Oilfield Services Data Dictionary (OSDD): https://www.apps.slb.com/cmd/units.aspx

The fallback, secondary source, is from our static snapshot of that page which lives in src/TotalDepth/common/data/osdd_units.json

When running tests with --runslow the tests.integration.common.test_units.test_slb_units_write_to_json test will re-populate that static data file.

This included currencies that all have zero offset and unit scale. Currencies: https://en.wikipedia.org/wiki/ISO_4217 ISO 4217 official currency codes in XML: https://www.currency-iso.org/dam/downloads/lists/list_one.xml

exception TotalDepth.common.units.ExceptionUnits¶: Base class exception for this module.

exception TotalDepth.common.units.ExceptionUnitsLookup¶: Raised if the unit lookup fails.

exception TotalDepth.common.units.ExceptionUnitsDimension¶: Raised if two units are of different dimensions.

class TotalDepth.common.units.Unit¶

Represents one row in the table at https://www.apps.slb.com/cmd/units.aspx

Examples:

Code    Name                Standard Form   Dimension   Scale               Offset
DEGC    'degree celsius'    degC            Temperature 1                   -273.15
DEGF    'degree fahrenheit' degF            Temperature 0.555555555555556   -459.67
DEGK    'kelvin'            K               Temperature 1                   0
DEGR    'degree rankine'    degR            Temperature 0.555555555555556   0

There will also be an entry for RP66V1 files:

degF    'degree fahrenheit' "5/9 degC +32"  Temperature 0.555555555555556   -459.67

So conversion from, say DEGC to DEGF is:

((value - DEGC.offset) * DEGC.scale) / DEGF.scale + DEGF.offset

((0.0 - -273.15) * 1.0) / 0.555555555555556 + -459.67 == 32.0

code¶: Alias for field number 0

name¶: Alias for field number 1

standard_form¶: Alias for field number 2

dimension¶: Alias for field number 3

scale¶: Alias for field number 4

offset¶: Alias for field number 5

is_primary¶: True if this is looks like a primary unit.

has_offset() → bool¶: True if this has an offset, for example DEGC. False otherwise, for example metres.

__getnewargs__()¶: Return self as a plain tuple. Used by copy and pickle.

static __new__(_cls, code: str, name: str, standard_form: str, dimension: str, scale: float, offset: float)¶: Create new instance of Unit(code, name, standard_form, dimension, scale, offset)

__repr__()¶: Return a nicely formatted representation string

TotalDepth.common.units.osdd_data_file_path() → str¶: Path to our static snapshot of the OSDD units page.

TotalDepth.common.units.read_osdd_static_data() → Dict[str, TotalDepth.common.units.Unit]¶: Read our static snapshot of the OSDD units page.

TotalDepth.common.units.slb_load_units()¶: Eagerly load the units into the cache.

TotalDepth.common.units.has_slb_units(unit_code: str) → bool¶: Returns True if the Schlumberger Unit exists.

TotalDepth.common.units.slb_units(unit: str) → TotalDepth.common.units.Unit¶: Returns the Schlumberger Unit corresponding to the unit code.

TotalDepth.common.units.has_slb_standard_form(standard_form: str) → bool¶: Returns True if an entry for the standard form exists.

TotalDepth.common.units.slb_standard_form_to_unit_code(standard_form: str) → List[TotalDepth.common.units.Unit]¶: Returns the unit(s) corresponding to the standard form. Example given ‘degC’ this returns the Units corresponding to [‘DEGC’, ‘deg C’, ‘oC’].

TotalDepth.common.units.same_dimension(a: TotalDepth.common.units.Unit, b: TotalDepth.common.units.Unit) → bool¶: Returns True if both units have the same dimension.

TotalDepth.common.units.convert(value: float, unit_from: TotalDepth.common.units.Unit, unit_to: TotalDepth.common.units.Unit) → float¶

Converts a value from one unit to another.

Examples:

Code    Name                Standard Form   Dimension   Scale               Offset
DEGC    'degree celsius'    degC            Temperature 1                   -273.15
DEGF    'degree fahrenheit' degF            Temperature 0.555555555555556   -459.67

So conversion from, say DEGC to DEGF is:

((value - DEGC.offset) * DEGC.scale) / DEGF.scale + DEGF.offset

((0.0 - -273.15) * 1.0) / 0.555555555555556 + -459.67 == 32.0

TotalDepth.common.units.convert_function(unit_from: TotalDepth.common.units.Unit, unit_to: TotalDepth.common.units.Unit) → Callable¶: Return a partial function to convert from one units to another.

TotalDepth.common.units.convert_array(array: numpy.ndarray, unit_from: TotalDepth.common.units.Unit, unit_to: TotalDepth.common.units.Unit) → numpy.ndarray¶: Convert an array of values.

TotalDepth.common.units.convert_array_inplace(array: numpy.ndarray, unit_from: TotalDepth.common.units.Unit, unit_to: TotalDepth.common.units.Unit) → None¶: Convert an array of values in-place.