p12_17.dir

来自「Programs for the book Advanced Engineeri」· DIR 代码 · 共 26 行

% partial derivative
>>df=((1.1)^3-(.9)^3)
df =

    0.6020

>>dfx=df/.2
dfx =

    3.0100

>>% Reduce stepsize
>>df=((1.01)^3-(.99)^3)
df =

    0.0600

>>dfx=df/.02
dfx =

    3.0001

>>exit
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