,hE SS/rSSKJrJrJrJrJrJr \/SQ- rSSKJ r \S/- rSSK J r J r J r \/SQ- rSSKJr \S/- rSS KJrJrJr \/S Q- rS rS rS rS rg)IQ)ContrastMatrix TreatmentPolySumHelmertDiff)Cr )center standardizescale)bsr)crcctecU$)a}The identity function. Simply returns its input unchanged. Since Patsy's formula parser ignores anything inside a function call syntax, this is useful to 'hide' arithmetic operations from it. For instance:: y ~ x1 + x2 has ``x1`` and ``x2`` as two separate predictors. But in:: y ~ I(x1 + x2) we instead have a single predictor, defined to be the sum of ``x1`` and ``x2``.)xs aC:\Users\julio\OneDrive\Documentos\Trabajo\Ideas Frescas\venv\Lib\site-packages\patsy/builtins.pyrr"s  HcB[S5S:Xde[S5beg)N)rrrrtest_Ir4s Q4199 T7??rcSSKJn URS5nURU$![a [ SU<S35ef=f)aA way to 'quote' variable names, especially ones that do not otherwise meet Python's variable name rules. If ``x`` is a variable, ``Q("x")`` returns the value of ``x``. (Note that ``Q`` takes the *string* ``"x"``, not the value of ``x`` itself.) This works even if instead of ``x``, we have a variable name that would not otherwise be legal in Python. For example, if you have a column of data named ``weight.in.kg``, then you can't write:: y ~ weight.in.kg because Python will try to find a variable named ``weight``, that has an attribute named ``in``, that has an attribute named ``kg``. (And worse yet, ``in`` is a reserved word, which makes this example doubly broken.) Instead, write:: y ~ Q("weight.in.kg") and all will be well. Note, though, that this requires embedding a Python string inside your formula, which may require some care with your quote marks. Some standard options include:: my_fit_function("y ~ Q('weight.in.kg')", ...) my_fit_function('y ~ Q("weight.in.kg")', ...) my_fit_function("y ~ Q(\"weight.in.kg\")", ...) Note also that ``Q`` is an ordinary Python function, which means that you can use it in more complex expressions. For example, this is a legal formula:: y ~ np.sqrt(Q("weight.in.kg")) r)EvalEnvironmentrzno data named z found) patsy.evalrcapture namespaceKeyError NameError)namerenvs rrr9sIF+  ! !! $C<}}T"" <D:;;r0sv *OO LLC522 --D6//  $ )