From: Michael Orlitzky Date: Tue, 6 Nov 2012 01:50:22 +0000 (-0500) Subject: Update all doctests to use index[] notation instead of __call__. X-Git-Url: https://gitweb.michael.orlitzky.com/?a=commitdiff_plain;h=06e812539fab63e76463e299a5dd40f035d9ab05;p=sage.d.git Update all doctests to use index[] notation instead of __call__. --- diff --git a/mjo/symbol_sequence.py b/mjo/symbol_sequence.py index 7f6c9db..a645930 100644 --- a/mjo/symbol_sequence.py +++ b/mjo/symbol_sequence.py @@ -2,12 +2,13 @@ from sage.all import * class SymbolSequence: """ - A callable object which imitates a function from ZZ^n to a - sequence with n subscripts. + An iterable object which acts like a sequence of symbolic + expressions (variables). INPUT: - - ``name`` -- The sequence name. + - ``name`` -- The sequence name. For example, if you name the + sequence `x`, the variables will be called `x0`, `x1`,... - ``latex_name`` -- An optional latex expression (string) to use instead of `name` when converting the symbols to latex. @@ -17,80 +18,63 @@ class SymbolSequence: OUTPUT: - A callable object returning symbolic expressions. + An iterable object containing symbolic expressions. EXAMPLES: + The simplest use case:: + + sage: a = SymbolSequence('a') + sage: a[0] + a0 + sage: a[1] + a1 + Create coefficients for polynomials of arbitrary degree:: sage: a = SymbolSequence('a') - sage: p = sum([ a(i)*x^i for i in range(0,5)]) + sage: p = sum([ a[i]*x^i for i in range(0,5)]) sage: p a4*x^4 + a3*x^3 + a2*x^2 + a1*x + a0 Using a different latex name since 'lambda' is reserved:: sage: l = SymbolSequence('l', '\lambda') - sage: l(0) + sage: l[0] l0 - sage: latex(l(0)) + sage: latex(l[0]) \lambda_{0} Using multiple indices:: sage: a = SymbolSequence('a') - sage: a(0,1,2) + sage: a[0,1,2] a012 - sage: latex(a(0,1,2)) + sage: latex(a[0,1,2]) a_{0}_{1}_{2} - sage: [ a(i,j) for i in range(0,2) for j in range(0,2) ] + sage: [ a[i,j] for i in range(0,2) for j in range(0,2) ] [a00, a01, a10, a11] - If no index is given, an unsubscripted symbol is returned:: - - sage: a = SymbolSequence('a') - sage: a() - a - You can pass slice objects instead of integers to obtain a list of symbols:: sage: a = SymbolSequence('a') - sage: a(slice(5,7)) + sage: a[5:7] [a5, a6] This even works for the second, third, etc. indices:: sage: a = SymbolSequence('a') - sage: a(slice(0,2), slice(0,2)) + sage: a[0:2, 0:2] [a00, a01, a10, a11] - You can also index with the list index operator:: - - sage: a = SymbolSequence('a') - sage: a[1] - a1 - - This allows you to retrieve one-dimensional slices easily:: - - sage: a = SymbolSequence('a') - sage: a[0:5] - [a0, a1, a2, a3, a4] - - If for whatever reason you prefer square brackets, the following - also works:: - - sage: a = SymbolSequence('a') - sage: a[1,3] - a13 - TESTS: We shouldn't overwrite variables in the global namespace:: sage: a = SymbolSequence('a') sage: a0 = 4 - sage: a(0) + sage: a[0] a0 sage: a0 4 @@ -100,16 +84,16 @@ class SymbolSequence: representation and compare because the output is unpredictable:: sage: a = SymbolSequence() - sage: a0str = str(a(0)) + sage: a0str = str(a[0]) sage: str(a(0)) == a0str True Slices and single indices work when combined:: sage: a = SymbolSequence('a') - sage: a(3, slice(0,2)) + sage: a[3, 0:2] [a30, a31] - sage: a(slice(0,2), 3) + sage: a[0:2, 3] [a03, a13] """