there is a error for solving equations

2 次查看(过去 30 天)
>> d = 'x^2 + 9*x –7 = 0'; >> solve(d) Error using solve>processString (line 354) ' x^2 + 9*x –7 = 0 ' is not a valid expression or equation.
Error in solve>getEqns (line 284) eqns = processString(eqns, v, vc);
Error in solve (line 160) [eqns,vars,options] = getEqns(varargin{:});

回答(2 个)

A Jenkins
A Jenkins 2014-6-6
When I copy/paste your code, I get that the '–' is the wrong character: it is the 'dash' (U+2013) character instead of the 'minus' (U+002D) character.
Does this work?
d = 'x^2 + 9*x - 7 = 0';
solve(d)

math search
math search 2014-6-6
Thank you it works now but how can you find names of that characters?

类别

Help CenterFile Exchange 中查找有关 Numerical Integration and Differential Equations 的更多信息

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by