secd vs sec
1 Ansicht (letzte 30 Tage)
Ältere Kommentare anzeigen
x=-89.5:0.001:89.5; y=1./secd(x); trapz(x,y) Gives 114
AND
x=-pi/2:0.001:pi/2; y=1./sec(x); trapz(x,y) Gives 2
Why?
0 Kommentare
Akzeptierte Antwort
Geoff
am 11 Mai 2012
Because your data ranges are different.
The area underneath the curve spanning -89.5:0.001:89.5 is approximately 180/pi times larger than the area underneath the curve spanning -pi/2:0.001:pi/2.
Your answers are correct, except you are using two different ranges. Surely the comparable range in degrees is -90:0.001:90
Note also that the step size for your degrees makes that calculation much more accurate than your radians range (which is using the same step size).
[edit] Compare apples with apples...
xd = -90:0.001:90;
yd = 1./secd(xd);
xr = xd * pi / 180;
yr = 1./sec(xr);
% Use radians for x-axis in both calculations
zd = trapz(xr, yd)
zr = trapz(xr, yr)
0 Kommentare
Weitere Antworten (0)
Siehe auch
Kategorien
Mehr zu Numerical Integration and Differentiation finden Sie in Help Center und File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!