Online Algebra Calculator
Many of users do not use powerful Maxima computer algebra system for systematic work, but for ad hoc algebraic calculations – equations, functions, matrixes, etc. only. To do this job, it is not useful to download the whole application from a web site.
-- Option variable: modulus Default value: false
When modulus is a positive number <p>, operations on rational numbers (as returned by rat and related functions) are carried out modulo <p>, using the so-called "balanced" modulus system in which <n> modulo <p> is defined as an integer <k> in [-(<p>-1)/2, ..., 0, ..., (<p>-1)/2] when <p> is odd, or [-(<p>/2 - 1), ..., 0, ...., <p>/2] when <p> is even, such that <a> <p> + <k> equals <n> for some integer <a>.
![Modulus Example m:matrix([0,3,3,-2,-4,-3],[0,4,-5,4,-3,-1],[0,-3,5,-1,-1,-4],[0,-3,1,2,0,-3],[0,-5,-1,-4,-1,-1],[0,5,0,-2,-3,-4]);
nullspace(m) ,modulus:11;](http://maxima-online.org//plot.html?g=i1419426188.png&t=img&db=r-1526896046)
If <expr> is already in canonical rational expression (CRE) form when modulus is reset, then you may need to re-rat <expr>, e.g., expr: rat (ratdisrep (expr)), in order to get correct results.
Typically modulus is set to a prime number. If modulus is set to a positive non-prime integer, this setting is accepted, but a warning message is displayed. Maxima will allow zero or a negative integer to be assigned to modulus, although it is not clear if that has any useful consequences.
(%o1) true (%i2)