When I integrate a constant over Tp I should get the constant but I don't?

I'm attempting to find the average value but have come up against a error.

When I integrate a constant over Tp I should get the constant but I don't?

>> T= 2*pi

>> ao=(1/T)*int(100.0,t,0,T) %Integrate the constant 100 over Tp to find the average

ao =

(143354028480566475*pi)/4503599627370496

Answer 1

[Stephan]

Hi,

int is a Symbolic Toolbox function. Use either double or integral for direct numeric computation.

a0 = double((1/T)*int(100.0,t,0,T))

[Gary Armstrong]

clear all

syms t n

T= 2*(pi); % T= Period

w0=1; % Fundamental anguler freg

%n=1:10; % n=1 fundamental, n>1 harmonics

v =100+100*cos(w0*t);

a0= double( (1/T)*int(v(t),t,0,T))

an= double( (2/T)*int(v(t)*cos(n*w0*t),t,0,T))

bn= double( (2/T)*int(v(t)*sin(n*w0*t),t,0,T))

Error using sym/subsindex (line 825)

Invalid indexing or function definition. Indexing must follow MATLAB indexing. Function arguments must be

symbolic variables, and function body must be sym expression.

Error in sym/subsref (line 870)

R_tilde = builtin('subsref',L_tilde,Idx);

[Stephan]

syms t n
T= 2*sym('pi'); % T= Period
w0=1;           % Fundamental anguler freg
n=1:10;         % n=1 fundamental, n>1 harmonics
v =100+100*cos(w0*t);
a0= 1/T*int(v,t,0,T)
an= 2/T*int(v*cos(n*w0*t),t,0,T)
bn= 2/T*int(v*sin(n*w0*t),t,0,T)

Answer 2

[Walter Roberson]

syms t
T = 2 * sym('pi');     %use symbolic pi instead of numeric pi
ao=(1/T)*int(100.0,t,0,T) 

[Gary Armstrong]

clear all

syms t n

T= 2*sym('pi'); % T= Period

w0=1; % Fundamental anguler freg

%n=1:10; % n=1 fundamental, n>1 harmonics

v =100+100*cos(w0*t);

a0= double( (1/T)*int(v(t),t,0,T))

an= double( (2/T)*int(v(t)*cos(n*w0*t),t,0,T))

bn= double( (2/T)*int(v(t)*sin(n*w0*t),t,0,T))

Error using sym/subsindex (line 825)

Invalid indexing or function definition. Indexing must follow MATLAB indexing. Function arguments must be

symbolic variables, and function body must be sym expression.

Error in sym/subsref (line 870)

R_tilde = builtin('subsref',L_tilde,Idx);

[Walter Roberson]

v is an expression not a function but you use v(t)