B Afxa50@sdZddlmZddlZddlZddlmZmZddlm Z m Z m Z m Z m Z ddlmZmZddlmZdd lmZmZmZe rdd lmZdd lmZdd lmZed ZedZdddddZGdddZ GdddeZ!dS)z pint.context ~~~~~~~~~~~~ Functions and classes related to context definitions and application. :copyright: 2016 by Pint Authors, see AUTHORS for more details.. :license: BSD, see LICENSE for more details. ) annotationsN)ChainMap defaultdict) TYPE_CHECKINGAnyCallableOptionalTuple) DefinitionUnitDefinition)DefinitionSyntaxError) ParserHelperSourceIteratorto_units_container)Quantity) UnitRegistry)UnitsContainerzF@context\s*(?P\(.*\))?\s+(?P\w+)\s*(=(?P.*))*z[A-Za-z_][A-Za-z0-9_]*strzCallable[..., Quantity[Any]])eqreturncsdddddfdd }|S)Nrrz Quantity[Any])uregvaluekwargsrcs|jfd|i|S)Nr)Zparse_expression)rrr)r+lib/python3.7/site-packages/pint/context.pyfunc%sz%_expression_to_function..funcr)rrr)rr_expression_to_function$src@seZdZdZd!dddddd d Zeddd d d ZedefddddZddddZ ddddZ e ddddZ ddZ dddddZdddd ZdS)"ContextaA specialized container that defines transformation functions from one dimension to another. Each Dimension are specified using a UnitsContainer. Simple transformation are given with a function taking a single parameter. Conversion functions may take optional keyword arguments and the context can have default values for these arguments. Additionally, a context may host redefinitions: A redefinition must be performed among units that already exist in the registry. It cannot change the dimensionality of a unit. The symbol and aliases are automatically inherited from the registry. Parameters ---------- name : str or None, optional Name of the context (must be unique within the registry). Use None for anonymous Context. (Default value = None). aliases : iterable of str Other names for the context. defaults : None or dict Maps variable names to values. Example ------- >>> from pint.util import UnitsContainer >>> from pint import Context, UnitRegistry >>> ureg = UnitRegistry() >>> timedim = UnitsContainer({'[time]': 1}) >>> spacedim = UnitsContainer({'[length]': 1}) >>> def time_to_len(ureg, time): ... 'Time to length converter' ... return 3. * time >>> c = Context() >>> c.add_transformation(timedim, spacedim, time_to_len) >>> c.transform(timedim, spacedim, ureg, 2) 6.0 >>> def time_to_len_indexed(ureg, time, n=1): ... 'Time to length converter, n is the index of refraction of the material' ... return 3. * time / n >>> c = Context(defaults={'n':3}) >>> c.add_transformation(timedim, spacedim, time_to_len_indexed) >>> c.transform(timedim, spacedim, ureg, 2) 2.0 >>> c.redefine("pound = 0.5 kg") Nrz Optional[str]zTuple[str, ...]zOptional[dict]None)namealiasesdefaultsrcCs6||_||_i|_|pi|_g|_d|_t|_dS)NF) r r!funcsr" redefinitionscheckedweakrefWeakValueDictionaryrelation_to_context)selfr r!r"rrr__init___s zContext.__init__)contextrcKsT|rPt|jf|}||j|j|}|j|_|j|_x|jD]}||j|<q:W|S|S)aCreates a new context that shares the funcs dictionary with the original context. The default values are copied from the original context and updated with the new defaults. If defaults is empty, return the same context. Parameters ---------- context : pint.Context Original context. **defaults Returns ------- pint.Context )dictr"r r!r#r$r()clsr+r"ZnewdefcZedgerrr from_contextys zContext.from_context)rc st|}t|\}}y`t|}|d}|d}|rbtdd|ddD}nd}|d} Wn4tk r} zt d||d | Wdd} ~ XYnX| r:d d | } y0d d| d dD} fdd| D} Wn>t t fk r*} zt d| d|d | Wdd} ~ XYnX|||| } n |||} t } x<|D]2\}}d|krt| |qRy|d\}}| t|t|}d|krfdd|dD\}}|r||}||}| |||| |||nPd|krBfdd|dD\}}|r2||}||}| |||ntWn:tk r} zt d||f|d | Wdd} ~ XYnXqRW| r| t | }|rt d|d| S)Nr r!css|]}|VqdS)N)strip).0arrr sz%Context.from_lines..=rr"z'Could not parse the Context header '%s')linenocSst|}|js|jS|S)N)compleximagreal)valrrrto_numsz"Context.from_lines..to_numcss|]}|dVqdS)r4N)split)r1partrrrr3sz(),cs"i|]\}}|t|qSr)rr0)r1kv)r:rr sz&Context.from_lines..z.Could not parse Context definition defaults: '':z<->c3s|]}t|VqdS)N)r from_string)r1s) non_int_typerrr3sz->c3s|]}t|VqdS)N)rrC)r1rD)rErrr3sz(Could not parse Context %s relation '%s'zContext parameters z not found in any equation)rnext _header_research groupdictr0tupler; Exceptionr ValueError TypeErrorsetredefineupdate _varname_refindallradd_transformationkeys)r-linesZ to_base_funcrEr5headerrr r!r"excZtxtctxnameslineZrelrrsrcdstZ missing_parsr)rEr:r from_liness~   "          zContext.from_linescCs$|||}||j|<||j|<dS)z-Add a transformation function to the context.N)__keytransform__r#r()r)r\r]r_keyrrrrSs  zContext.add_transformationcCs |||}|j|=|j|=dS)z-Add a transformation function to the context.N)r_r#r()r)r\r]r`rrrremove_transformations zContext.remove_transformationz%Tuple[UnitsContainer, UnitsContainer]cCst|t|fS)N)r)r\r]rrrr_szContext.__keytransform__cCs"|||}|j|||f|jS)zTransform a value.)r_r#r")r)r\r]registryrr`rrr transforms zContext.transformr) definitionrcCsnxh|D]\}t|}t|ts2td||j|jksD|j rLtd|j rZtd|j |q WdS)zOverride the definition of a unit in the registry. Parameters ---------- definition : str = ``, e.g. ``pound = 0.5 kg`` z%Expected = ; got %sz8Can't change a unit's symbol or aliases within a contextz(Can't define base units within a contextN) splitlinesr rC isinstancer r r0symbolr r!Zis_baser$append)r)rdr[drrrrOs   zContext.redefinezBTuple[Optional[str], Tuple[str, ...], frozenset, frozenset, tuple]cCs:|jt|jtdd|jDt|jt|jfS)a.Generate a unique hashable and comparable representation of self, which can be used as a key in a dict. This class cannot define ``__hash__`` because it is mutable, and the Python interpreter does cache the output of ``__hash__``. Returns ------- tuple css|]\}}|t|fVqdS)N)id)r1r>r?rrrr3,sz#Context.hashable..)r rJr! frozensetr#itemsr"r$)r)rrrhashables  zContext.hashable)NrN)__name__ __module__ __qualname____doc__r* classmethodr/floatr^rSra staticmethodr_rcrOrmrrrrr+s2Xrcs`eZdZdZfddZddZdddd d Zed d Zed dZ ddZ ddZ Z S) ContextChainzvA specialized ChainMap for contexts that simplifies finding rules to transform from one dimension to another. cs$tg|_|jd|_dS)N)superr*contextsmapsclear_graph)r)) __class__rrr*7s  zContextChain.__init__cGs8tt||j|_ddt|D|j|_d|_dS)aInsert one or more contexts in reversed order the chained map. (A rule in last context will take precedence) To facilitate the identification of the context with the matching rule, the *relation_to_context* dictionary of the context is used. cSsg|] }|jqSr)r()r1rYrrr Fsz0ContextChain.insert_contexts..N)listreversedrwrxrz)r)rwrrrinsert_contexts=szContextChain.insert_contextsNint)ncCs"|jd|=|jd|=d|_dS)zRemove the last n inserted contexts from the chain. Parameters ---------- n: int (Default value = None) N)rwrxrz)r)rrrrremove_contextsIs  zContextChain.remove_contextscCsx|D]}|jSWiS)N)valuesr")r)rYrrrr"VszContextChain.defaultscCs<|jdkr6tt|_x |D]\}}|j||qW|jS)zThe graph relatingN)rzrrNadd)r)Zfr_Zto_rrrgraph\s   zContextChain.graphcCs|||f||||S)z|Transform the value, finding the rule in the chained context. (A rule in last context will take precedence) )rc)r)r\r]rbrrrrrceszContextChain.transformcCstdd|jDS)zGenerate a unique hashable and comparable representation of self, which can be used as a key in a dict. This class cannot define ``__hash__`` because it is mutable, and the Python interpreter does cache the output of ``__hash__``. css|]}|VqdS)N)rm)r1rYrrrr3psz(ContextChain.hashable..)rJrw)r)rrrrmkszContextChain.hashable)N) rnrorprqr*rrpropertyr"rrcrm __classcell__rr)r{rru2s    ru)"rqZ __future__rrer& collectionsrrtypingrrrrr Z definitionsr r errorsr utilrrrZquantityrrbrrcompilerGrQrrrurrrr s(