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\usepackage{pgfplots}
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\begin{document}
\begin{tikzpicture}
\begin{axis}[xlabel={$g$},ylabel={$\mathcal{M}_2$},title={$\mathcal{M}_2$ v.s. $g$ },tick align=inside,legend style={at={(0.2,1.2)},anchor=north},grid={both}]\addplot[color=blue,mark=*,smooth] coordinates {(-0.2324768366025517, 0.010179027166607601) (-0.2174768366025518, 0.012700677518416869) (-0.20247683660255178, 0.015914929866794172) (-0.18747683660255177, 0.020024212927263287) (-0.17247683660255175, 0.02528791586737733) (-0.15747683660255174, 0.032034550069390655) (-0.14247683660255173, 0.04067294569286466) (-0.1274768366025517, 0.05169871325524065) (-0.11247683660255181, 0.06568911429733332) (-0.09747683660255169, 0.08327519508063366) (-0.08247683660255178, 0.10507537532282413) (-0.06747683660255177, 0.13157250926463754) (-0.05247683660255176, 0.16292287590693638) (-0.037476836602551744, 0.19870953869174304) (-0.02247683660255173, 0.2376998361713844) (-0.0074768366025518285, 0.27772582130124907) (0.007523163397448296, 0.31583345964325205) (0.022523163397448198, 0.348777714878471) (0.03752316339744832, 0.37375895572844275) (0.052523163397448225, 0.3891051689553718) (0.06752316339744824, 0.3945830900350399) (0.08252316339744825, 0.39122799220737287) (0.09752316339744815, 0.38084991622703784) (0.11252316339744828, 0.36548868544182306) (0.12752316339744818, 0.3470148330281814) (0.1425231633974483, 0.32693104318822336) (0.1575231633974482, 0.3063316700703259) (0.17252316339744822, 0.2859505784494) (0.18752316339744823, 0.26624121060662875) (0.20252316339744825, 0.247456486000428) (0.21752316339744826, 0.22971483114393784)};
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\end{axis}
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\end{document}