linear buckling calculation

[coveralls]

Pull Request Test Coverage Report for Build 164

• 721 of 755 (95.5%) changed or added relevant lines in 4 files are covered.
• 6 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-1.4%) to 96.726%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
feBeam2d.go	81	90	90.0%
model.go	302	327	92.35%
<!--	Total:	721	755	95.5%	-->

Files with Coverage Reduction	New Missed Lines	%
model.go	6	91.23%
<!--	Total:	6		-->

Totals
Change from base Build 116:	-1.4%
Covered Lines:	1743
Relevant Lines:	1802

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💛 - Coveralls