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gives the Klein invariant modular elliptic function J(tau).
  • Mathematical function, suitable for both symbolic and numerical manipulation.
  • The argument tau is the ratio of Weierstrass half-periods omega^′/omega.
  • J(tau) is invariant under any combination of the modular transformations tau→tau+1 and tau→-1/tau.
  • For certain special arguments, KleinInvariantJ automatically evaluates to exact values.
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