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IPLT

This constant allows redefinition of the principal solution measure, which is printed as the second (real) column in the screen output and in the fort.7 output-file :

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If IPLT = 0 then the $ L_2$-norm is printed. Most demos use this setting. For algebraic problems, the standard definition of $ L_2$-norm is used. For differential equations, the $ L_2$-norm is defined as

$\displaystyle \sqrt{ \int_0^1 \sum_{k=1}^{NDIM} U_k(x)^2 ~ dx}~.$

Note that the interval of integration is $ [0,1]$, the standard interval used by AUTO. For periodic solutions the independent variable is transformed to range from 0 to 1, before the norm is computed. The AUTO-constants THL(*) and THU(*) (see Section 10.5.5 and Section 10.5.6) affect the definition of the $ L_2$-norm.
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If 0 $ <$ IPLT $ \le$ NDIM then the maximum of the IPLT'th solution component is printed.
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If $ -$NDIM $ \le$ IPLT $ <$0 then the minimum of the IPLT'th solution component is printed. (Demo fsh.)
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If NDIM $ <$ IPLT $ \le$ 2*NDIM then the integral of the (IPLT$ -$NDIM)'th solution component is printed. (Demos exp, lor.)
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If 2*NDIM $ <$ IPLT $ \le$ 3*NDIM then the $ L_2$-norm of the (IPLT$ -$NDIM)'th solution component is printed. (Demo frc.)

Note that for algebraic problems the maximum and the minimum are identical. Also, for ODEs the maximum and the minimum of a solution component are generally much less accurate than the $ L_2$-norm and component integrals. Note also that the routine PVLS provides a second, more general way of defining solution measures; see Section 10.7.10.


next up previous contents
Next: NUZR Up: Output Control. Previous: IID   Contents
Gabriel Lord 2007-11-19