Adding two functions
in [Matlab]
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From: Raymond's Group Lee on 16 Apr 2010 10:36 I am wondering there is anyway we can add 2 functions, f(x) and g(x), together. f = @(x) x ; g = @(x) x^2 ; h = @(x) f + g ; This does not work. If this is possible, I can use it to define function like f(x) = x + x^2 + x^3 + ...+ x^100 + ... + x^1000 ; Thanks.
From: Steven Lord on 16 Apr 2010 11:01 "Raymond's Group Lee" <jh52lee(a)uwaterloo.ca> wrote in message news:hq9sl5$5aq$1(a)fred.mathworks.com... >I am wondering there is anyway we can add 2 functions, f(x) and g(x), >together. > > > f = @(x) x ; > g = @(x) x^2 ; > h = @(x) f + g ; Addition is not defined for function handles. However, addition can be defined for _the values returned by two function handles_. f = @(x) x; g = @(x) x.^2; h = @(x) f(x) + g(x); > This does not work. > > If this is possible, I can use it to define function like > > f(x) = x + x^2 + x^3 + ...+ x^100 + ... + x^1000 ; Technically yes, although creating 1001 individual function handles to do so seems excessive, and I'd question the use of such a high degree polynomial on general principles. I'd use POLYVAL instead. -- Steve Lord slord(a)mathworks.com comp.soft-sys.matlab (CSSM) FAQ: http://matlabwiki.mathworks.com/MATLAB_FAQ
From: James Allison on 16 Apr 2010 11:01 Try: f = @(x) x ; g = @(x) x^2 ; h = @(x) f(x) + g(x) ; -James Raymond's Group Lee wrote: > I am wondering there is anyway we can add 2 functions, f(x) and g(x), > together. > > > f = @(x) x ; > g = @(x) x^2 ; > h = @(x) f + g ; > This does not work. > > If this is possible, I can use it to define function like > > f(x) = x + x^2 + x^3 + ...+ x^100 + ... + x^1000 ; > > Thanks.
From: Raymond's Group Lee on 16 Apr 2010 11:39 "Steven Lord" <slord(a)mathworks.com> wrote in message <hq9u3s$40i$1(a)fred.mathworks.com>... > > "Raymond's Group Lee" <jh52lee(a)uwaterloo.ca> wrote in message > news:hq9sl5$5aq$1(a)fred.mathworks.com... > >I am wondering there is anyway we can add 2 functions, f(x) and g(x), > >together. > > > > > > f = @(x) x ; > > g = @(x) x^2 ; > > h = @(x) f + g ; > > Addition is not defined for function handles. However, addition can be > defined for _the values returned by two function handles_. > > f = @(x) x; > g = @(x) x.^2; > h = @(x) f(x) + g(x); > > > This does not work. > > > > If this is possible, I can use it to define function like > > > > f(x) = x + x^2 + x^3 + ...+ x^100 + ... + x^1000 ; > > Technically yes, although creating 1001 individual function handles to do so > seems excessive, and I'd question the use of such a high degree polynomial > on general principles. I'd use POLYVAL instead. > > -- > Steve Lord > slord(a)mathworks.com > comp.soft-sys.matlab (CSSM) FAQ: http://matlabwiki.mathworks.com/MATLAB_FAQ > Thanks, Steve. That's a good way.
From: Raymond's Group Lee on 16 Apr 2010 11:39
"Steven Lord" <slord(a)mathworks.com> wrote in message <hq9u3s$40i$1(a)fred.mathworks.com>... > > "Raymond's Group Lee" <jh52lee(a)uwaterloo.ca> wrote in message > news:hq9sl5$5aq$1(a)fred.mathworks.com... > >I am wondering there is anyway we can add 2 functions, f(x) and g(x), > >together. > > > > > > f = @(x) x ; > > g = @(x) x^2 ; > > h = @(x) f + g ; > > Addition is not defined for function handles. However, addition can be > defined for _the values returned by two function handles_. > > f = @(x) x; > g = @(x) x.^2; > h = @(x) f(x) + g(x); > > > This does not work. > > > > If this is possible, I can use it to define function like > > > > f(x) = x + x^2 + x^3 + ...+ x^100 + ... + x^1000 ; > > Technically yes, although creating 1001 individual function handles to do so > seems excessive, and I'd question the use of such a high degree polynomial > on general principles. I'd use POLYVAL instead. > > -- > Steve Lord > slord(a)mathworks.com > comp.soft-sys.matlab (CSSM) FAQ: http://matlabwiki.mathworks.com/MATLAB_FAQ > Thanks, Steve. That's a good way. |