For questions specific to Version 7 of Mathematica.
6
votes
0answers
67 views
Mathematica 7: “LessEqual::nord:” error when using NMinimize on a real function
I encounter a problem (Mathematica 7) similar to Strategies to avoid LessEqual::nord in NMinimize? but the advised strategies don't work for me. Also, I get different results with different ...
4
votes
0answers
155 views
NullSpace[_, Method->“OneStepRowReduction”] is sometimes wrong; how can I work out when this happens?
(This is on MMA 7.0.1.0 on OS X)
I've just found a large matrix m for which NullSpace[m] and ...
3
votes
0answers
75 views
An recurrence equation that can be solved in version 7 but not in version 8
A friend of mine showed me this code sample:
RSolve[{a[n] == a[n - 5] + 1, Sequence @@ Table[a[i] == 1, {i, 5}]}, a[n], n] // Timing
It's solved by version 7 in ...
2
votes
0answers
282 views
Simple contour integral with a parameter gone wrong
I run into the following problem, I tried to evaluate a very simple integral:
Assuming[ a > 0 , Integrate[Sin[a*s]/(s - I)^2, {s, -Infinity, Infinity}]]
...
0
votes
0answers
67 views
Error changing edge thickness in a GraphPlot
I'm having some problems with the Mathematica graphics inspector. I want to make a graph with the following code:
...
