git push -u origin main

2026-03-19 14:05:33 +08:00
commit 1e30b7bc63
739 changed files with 572150 additions and 0 deletions
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+      FUNCTION EXPINT(X)
+C     ==================
+C
+C     First exponential integral function E1(X)
+C
+      INCLUDE 'PARAMS.FOR'
+C
+      IF(X.LE.1.0) THEN
+         EXPINT=-LOG(X)-0.57721566+X*(0.99999193+X*(-0.24991055
+     *          +X*(0.05519968+X*(-0.00976004+X*0.00107857))))
+       ELSE
+         EXPINT=EXP(-X)*((0.2677734343+X*(8.6347608925+X*
+     *          (18.059016973+X*(8.5733287401+X))))/
+     *          (3.9584969228+X*(21.0996530827+X*
+     *          (25.6329561486+X*(9.5733223454+X)))))/X
+      END IF
+      RETURN
+      END