Category : BASIC Source Code
Archive   : UBAS830.ZIP
Filename : ALGEQ.UB


˜Å algeq by S.A.
(ŸÞñÈÀ©ñ
d™" * Solve algebraic equations of real coefficients *"
¢(™" * input example : x^3+2.3*x+4.1 *"À™
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[ȃXфXƒI)À™" X("Á€ìƒE)ƒIÁ")= "Á€ìƒUS)ƒXÁ
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õAlgEq(ƒNÂ&„AÂ&„X)

ºƒN1ƒN2ƒBƒC
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9"
ƒN1уN
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ˆõQfac×ó(„A)ÀƒN2Ññ

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ˆõQuad½ó(ƒBƒC)ÀƒN2ÝÑñÀƒN1ÞÑñ
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XƒN1ÓñŽˆõQfac×ó(„B1)À‡ñ6

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õQuad(ƒBƒC)
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ºƒIƒCtƒRTƒMl
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: ƒX1фB1ƒN1Þñ
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D ˜¼
.N ƒDetуA1åƒD1ރB1åƒC1
TX ƒX2Ñ(ƒD1åƒX1ރB1åƒY1)æƒDet
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„l ˜1
Ÿv ƒBÝуX2ÀƒCÝуY2
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C¨ÀƒMlÑñ
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Z²ÀƒMlÑñ
À‡ñÖ

w¼ ƒRTÀ™"Retry"ÁƒRTÁÀ¬ð
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—ä˜
§îõNewton
ÕøºƒIƒKƒDifƒEps1ƒEps2ƒSXƒDX
üƒEps1рá€ïÂñ)ÀƒEps2рá€ïÂñ!)
 ‰ƒKÑñ
ŠƒN
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E  ò€¿„XƒK))ԃEps1Ž„XƒK)Ñð‡ñp
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ŠƒNÀƒSXуSXå„XƒK)݄AƒI)ÀŒ
Ú 4 ƒDXуNå„Að)À‰ƒIÑñ
ŠƒNÞñ
ÀƒDXуDXå„XƒK)Ý(ƒNރI)å„AƒI)ÀŒ
ò > ü€¿ƒDX)ԃEps2Ž
O
H À™" We cannot decide X("ÁƒKÁ") in full accuracy becase it is a multiple root."À‡ñp
d
R ƒDifуSXæƒDX
z
\ „XƒK)ÞуDif
Š
f“ƃDifÑð
‘
pŒ
˜
z•
¡
„˜
Ê
Ž˜ Using Bairstow-Hitchcock method
˜˜ It will give an suitably accurate answer in any POINT assignment.
@¢˜ The last digit may have an error.
€¬˜ The final stage (Newton's method) decreases the error,
Ƕ˜ but this routine may be an endless loop. If this is the case
óÀ˜ eliminate repeat-until in *Newton.