CoCalc Public Filessupport / 2014-10-25-assume.sagews
Authors: Harald Schilly, ℏal Snyder, William A. Stein
Description: Jupyter notebook support/2015-06-04-141749-bokeh.ipynb
a,b=var('a b') assume(4*b^2-4*a^2<0) assume((b-a)*(b+a)<0) integrate(1/(a-b*sin(x)),x,-oo,oo)
Error in lines 4-4 Traceback (most recent call last): File "/projects/4a5f0542-5873-4eed-a85c-a18c706e8bcd/.sagemathcloud/sage_server.py", line 841, in execute exec compile(block+'\n', '', 'single') in namespace, locals File "", line 1, in <module> File "/usr/local/sage/sage-6.3.beta6/local/lib/python2.7/site-packages/sage/misc/functional.py", line 799, in integral return x.integral(*args, **kwds) File "expression.pyx", line 10182, in sage.symbolic.expression.Expression.integral (build/cythonized/sage/symbolic/expression.cpp:44845) File "/usr/local/sage/sage-6.3.beta6/local/lib/python2.7/site-packages/sage/symbolic/integration/integral.py", line 699, in integrate return definite_integral(expression, v, a, b) File "function.pyx", line 914, in sage.symbolic.function.BuiltinFunction.__call__ (build/cythonized/sage/symbolic/function.cpp:8891) File "function.pyx", line 504, in sage.symbolic.function.Function.__call__ (build/cythonized/sage/symbolic/function.cpp:5761) File "/usr/local/sage/sage-6.3.beta6/local/lib/python2.7/site-packages/sage/symbolic/integration/integral.py", line 173, in _eval_ return integrator(*args) File "/usr/local/sage/sage-6.3.beta6/local/lib/python2.7/site-packages/sage/symbolic/integration/external.py", line 21, in maxima_integrator result = maxima.sr_integral(expression, v, a, b) File "/usr/local/sage/sage-6.3.beta6/local/lib/python2.7/site-packages/sage/interfaces/maxima_lib.py", line 788, in sr_integral self._missing_assumption(s) File "/usr/local/sage/sage-6.3.beta6/local/lib/python2.7/site-packages/sage/interfaces/maxima_lib.py", line 988, in _missing_assumption raise ValueError(outstr) ValueError: Computation failed since Maxima requested additional constraints; using the 'assume' command before evaluation *may* help (example of legal syntax is 'assume((b-a)*(b+a) >0)', see assume? for more details) Is (b-a)*(b+a) positive, negative or zero?