# Question:Parameters for controlling execution of numapprox[infnorm]?

## Question:Parameters for controlling execution of numapprox[infnorm]?

Maple

Hello Maple wizards,

I'm trying to use numapprox[infnorm] to locate the L-infinity norm of functions such g(y) on the range 0.0..1.0 at the bottom of this post. Plotting shows that the function has an range of width 10e-3 that contains a minimum near y=0.9965, but infnorm() doesn't find it unless the range is artifically constrained to be close to the minimum.  I'm using infnorm() in a proc's loop, so manual control of the range based on the graph is not an appealing option.

I am sure that infnorm uses some threshold delta and epsilon to control its search, but I see no reference to it, let alone how to control it. Is there a global parameter that I need to set, or do I need to generate the code (assuming it isn't a primitive). Am I better off using Optimize[Minimize]? I"m going to be doing a lot of these.

Thank you in advance for your insight,

- Jimmy

g := proc (y) options operator, arrow; 4252303.330970942593905031892274982282069454287739192062367115520907158043940467753366406803685329554*(.2060666007253544345532476096274315858885591823277283217936036927134849983514671941971645235740191230+1.000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000*y+(-1)*.2060666007253544345532476096274315858885591823277283217936036927134849983514671941971645235740191230*((1.+(-1)*9.705600000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000*y^2+9.705600000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000*y)^(1/2)))*y^(14707178/1411)+(-1)*1.*(2126151.6654854712969525159461375*(.70606660072535443455324760962743+.5000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000*y+(-1)*.2060666007253544345532476096274315858885591823277283217936036927134849983514671941971645235740191230*((11.740216960000000000000000000000+(-1)*16.627633920000000000000000000000*y+5.887416960000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000*y^2)^(1/2)))*y^(598589/1411)+2126151.6654854712969525159461375*(.70606660072535443455324760962743+.5000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000*y+(-1)*.2060666007253544345532476096274315858885591823277283217936036927134849983514671941971645235740191230*((11.740216960000000000000000000000+(-1)*16.627633920000000000000000000000*y+5.887416960000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000*y^2)^(1/2)))*y^9999)*(.500000000000000000000000000000009170505551618237656508386487125*(.70606660072535443455324760962743+.5000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000*y+(-1)*.2060666007253544345532476096274315858885591823277283217936036927134849983514671941971645235740191230*((11.740216960000000000000000000000+(-1)*16.627633920000000000000000000000*y+5.887416960000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000*y^2)^(1/2)))*y^(598589/1411)+.500000000000000000000000000000009170505551618237656508386487125*(.70606660072535443455324760962743+.5000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000*y+(-1)*.2060666007253544345532476096274315858885591823277283217936036927134849983514671941971645235740191230*((11.740216960000000000000000000000+(-1)*16.627633920000000000000000000000*y+5.887416960000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000*y^2)^(1/2)))*y^9999) end proc

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