Matlab求解包含阶跃函数的数值积分 求MATLAB数值积分
\u8bf7\u6559\u5404\u8def\u5927\u795e\uff0cmatlab\u7ea7\u6570\u6c42\u548c\u540e\uff0c\u6c42\u89e3\u6570\u503c\u79ef\u5206\u3002\u65b9\u6cd5/\u6b65\u9aa4
\u6700\u5e38\u89c1\u7684\u7ea7\u6570\u5f62\u5f0f\uff0c\u5982\u4e0b\u6240\u793a\u3002
S \uff1a\u7ea7\u6570\u7684\u548c
i\uff1a \u81ea\u53d8\u91cf\uff0c\u503c\u57df\u4e3a[a,b]
f(i)\uff1a\u4e3a\u5173\u4e8e\u81ea\u53d8\u91cfi\u7684\u51fd\u6570
\u67e5\u9605matlab\u5e2e\u52a9\u53ef\u4ee5\u77e5\u9053\uff0c\u53ef\u4ee5\u7528symsum\u51fd\u6570\u6c42\u89e3\u7ea7\u6570\uff0c\u51fd\u6570\u6709\u4ee5\u4e0b4\u79cd\u4f7f\u7528\u65b9\u5f0f\uff1a
\u4f5c\u4e3a\u793a\u4f8b\uff0c\u5c0f\u7f16\u91c7\u7528\u7b2c\u56db\u79cd\u65b9\u5f0f\u6c42\u89e3\u4ee5\u4e0b\u7ea7\u6570\uff1a
clc;clear;
% symsum(expr,v,a,b)
syms v
syms f
a = 1;
b = 100;
f = v^2;
S = symsum(f,v,a,b)
\u70b9\u51fb\u56fe\u4e2d\u7ea2\u8272\u7bad\u5934\u6240\u6307\u7684\u8fd0\u884c\u6309\u94ae\uff0c\u8ba1\u7b97\u7ed3\u679c\u4e3a\uff1a
S = 338350
\u901a\u8fc7int()\u51fd\u6570\u548cvpa()\u51fd\u6570\u6c42\u5f97K\u503c\uff08\u6570\u503c\u89e3\uff09\uff0c\u7136\u540e\u7528polt()\u51fd\u6570\u753b\u51fab\u3001K\u7684\u5173\u7cfb\u56fe\u3002
\u4ee3\u7801\u89c1\u9644\u4ef6\u3002
syms x
F=heaviside(x);
int(F,x,-10,10)
结果：
ans =
10
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