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 Mar 21 awarded Popular Question Jan 29 awarded Yearling Jan 7 comment How to write this code as a pure function? This gives some answer: MapThread[Insert, {#, Table[0, {Length[#]}], Table[2, {Length[#]}]}] &[ls] Jan 3 answered How to avoid 0 OverVector[F] to be evaluated as 0? Nov 14 comment Check an inequality if one condition holds The Reduce command says what for real parameters the statement is false: Reduce[{A < 1, Abs[[Beta]] < Abs[1 + 4 [Alpha]]}, {[Alpha], [Beta]}, Reals] Nov 14 comment Check an inequality if one condition holds What is assumed about $\alpha$ and $\beta$? Oct 13 comment Integral of DiracDelta giving an unusual answer Seems to be a bug. In V9 this produces the same answer. This Integrate[DiracDelta[a - x], {x, a - 1, b}, Assumptions -> {a, b} \[Element] Reals] - Integrate[DiracDelta[a - x], {x, a - 1, a}, Assumptions -> {a, b} \[Element] Reals] gives $\theta (b-a)-\theta (0)$. Oct 12 comment Integral of DiracDelta giving an unusual answer It's not. For Integrate[DiracDelta[x], {x, 0, 1}] Mma gives $\delta (0)$. But the value of $\int_0^1 \delta (x) \, dx$ is not defied. So what do you call the correct evaluation of the this integral? In the standard definition delta-function is not supposed to act on discontinuous functions. Oct 11 comment Integral of DiracDelta giving an unusual answer The result seems to incorrect, more specific command Integrate[DiracDelta[a - x], {x, a, b}, Assumptions -> a < b] gives HeavisideTheta[0]. But the question itself is incorrect, since delta-function is not well-defined on discontinuous function and Mma is asked about the application of $\delta[a-x]$ on the step HeavisideTheta[a-x]. Jan 29 awarded Yearling Jul 2 awarded Curious Feb 15 awarded Nice Answer Feb 10 revised How to increase range in Plot without exceeding maximum bounds? fixed code formatting Feb 10 suggested approved edit on How to increase range in Plot without exceeding maximum bounds? Feb 4 answered Partial differential equation with initial conditions Feb 3 comment Creating a function as a table of derivations @Pygmalion g = Function[D[f@@args,#]&/@args//Transpose//Evaluate] Feb 3 comment Creating a function as a table of derivations @Pygmalion One can use Function to get a function out of it. I've edited the answer. Feb 3 revised Creating a function as a table of derivations added 18 characters in body Feb 3 answered Creating a function as a table of derivations Jan 31 comment DSolve cannot solve for certain branches of the solution help pls One way is to try for numerical values of parameters. If for all constants say, equal to one, Mma couldn't find a solution, there seems to be no sense trying the general case. At least before solving a concrete system.