Questions about Mathematica's predicate functions.
8
votes
2answers
435 views
How does Mathematica decide that Log[2,8] is integer?
At school we learned that $\log_b(x)=\log(x)/\log(b)$, which is implemented in Mathematica as Log[b, x], but the results are different.
...
14
votes
1answer
309 views
_?NumericQ equivalent for lists
A few months ago I got a simple answer (see: 1 ) to the question of how to force numeric evaluation during use of functions such as NMinimize - namely the use of _?NumericQ in the argument list.
I ...
2
votes
1answer
62 views
How to work with the symbol EndOfFile? [duplicate]
How to work with the symbol EndOfFile? I want to use the EndOfFile symbol to determine when my control structure reaches the end ...
2
votes
1answer
90 views
9
votes
5answers
797 views
Fastest square number test
What is the fastest possible square number test in Mathematica 7, both for machine size and big integers?
I presume in version 8 the fastest will be a dedicated C LibraryLink function.
5
votes
2answers
189 views
Why is an integer not considered as a real?
Please consider the following:
zeros={0.,0};
data={1, 0., 0};
DeleteCases[data, #]&/@zeros
Head/@zeros
(*{Real, Integer}*)
(*{{1, 0}, {1, 0.}}*)
For my ...
5
votes
1answer
87 views
lists of conditions
I have got coordinates in two list of Latitude and Longitude and would
like to check if those coordinates are in a certain grid
Example lists are:
...
0
votes
1answer
55 views
What is the most elegant way to see if an expression is affected by a certain symbol? [duplicate]
Possible Duplicate:
Determine whether some expression contains a given symbol
Let's say I have some expression:
sample = {1, 1/q, f[m]}
And I want to ...
8
votes
2answers
236 views
15
votes
8answers
537 views
How do you check if there are any equal arguments(even sublist) in a list?
I would like to set up a function which has to return True if at least two arguments of a given List are equal.
So if I give {1,4,6,2} to the function it has to ...
17
votes
4answers
514 views
Why does Mathematica claim there is no even prime?
I wonder if this is a bug, or if I'm misunderstanding something:
Exists[n, EvenQ[n] && PrimeQ[n]] // Resolve
(*
==> False
*)
So if I interpret this ...
2
votes
2answers
76 views
Using FreeQ with implicit functions
In Mathematica 7, I want to determine whether a list of free of numbers greater than 1 or not. It seems like using FreeQ would be a concise way to do this:
...
10
votes
1answer
171 views
Why does Assuming[x > 0, TrueQ[x > 0]] return False?
Assuming[x>0,TrueQ[x>0]]
should, as I understand it, test TrueQ[x>0] after assuming ...
