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| Dear MMAers: Generate a symbol: In[255]:= Symbol["x" "1"] Out[255]= x1 Assign a value: In[256]:= Symbol["x" "1"] = 45 During evaluation of In[256]:= Set::write: Tag Symbol in Symbol[x1] is Protected. >> ... |
| Say I have a function: test[x_] := Block[{x}, ToExpression["test" "State"]; testState = 67] testState is a global that test can refer to to see its last state: In[133]:= testState Out[133]= 67 *Test* needs to be used... |
| I want to have a list of expressions that are to be evaluated in a module. So as not to have the variables in the input expressions take on global values, the plan is to input the expressions as strings. Here is a simplified program of the problem:... |
| a = v v a b /. a_ b_ -> a + b 2 v The expected answer is v + b Maybe something about the global 'a' is interfering with the substitutions. Make 'a' and 'b' local variables in a module: times2plus[expr_] := Module[{a, b}, ... |
| Mathematica doesn't use the usual boolean notation with which circuit designers are familiar. The plan is to enter boolean expression as a c d + b d not a + a not b not c (a not c not d + b not c not d) and produce overbars on the... |
| Hi, This is an idea that has challenged me since I started using MMA a little over two years ago. The idea was to append `//stereo` to a 3D plot and instantly get a stereogram that can be manipulated just like a normal 3D plot, turning it around... |
| Hi, I have a lot of utility functions that I'd like to make into an Algebraic Manipulation Extras. For example, it would be nice to have a crossMultiply: crossMultiply[a_==b_]:=Numerator[a] Denominator[b]==Numerator[b] Denominator[a] ... |
| Suppose you have `3x^3 + 6x^3 + a 6x^3` and you want to replace all the terms with 6x^3 by zero. This works: In[1]:= HoldForm[3 x^3 + 6 x^3 + a 6 x^3]/. 6x^3->0//ReleaseHold Out[1]= 3 x^3 But if you have: In[2]:= var=3 x^3 + 6... |
| In my thread *A rule such that x+x^2/.x->0 gives x^2* , I came to the part where I wanted to create an Infix operator to work like ReplaceAll orr ReplaceRepeated, thinking that the next logical operator would be ///. It turns out that this is not... |
| The normal behaviour of ReplaceAll as in n[1]:= x+x^2/.x->0 Out[1]= 0 makes it impossible to deal with x^1 separately. But x^2 can be replaced as in In[2]:= x+x^2/.x^2->0 Out[2]= x The Replace function, operating at level... |