STELLOPT: Added missing chisq_rosenbrock2d file.

STELLOPTV2/Sources/Chisq/chisq_rosenbrock2d.f90

@@ -0,0 +1,57 @@
+!-----------------------------------------------------------------------
+!     Subroutine:    chisq_rosenbrock2D
+!     Authors:       S. Lazerson ([email protected])
+!     Date:          2023
+!     Description:   This is a 2D Rosenbrock function see:
+!                    https://en.wikipedia.org/wiki/Rosenbrock_function
+!-----------------------------------------------------------------------
+      SUBROUTINE chisq_rosenbrock2d(target,sigma,niter,iflag)
+!-----------------------------------------------------------------------
+!     Libraries
+!-----------------------------------------------------------------------
+      USE stellopt_runtime
+      USE stellopt_targets
+      USE stellopt_vars
+
+!-----------------------------------------------------------------------
+!     Input/Output Variables
+!
+!-----------------------------------------------------------------------
+      IMPLICIT NONE
+      REAL(rprec), INTENT(in)    ::  target
+      REAL(rprec), INTENT(in)    ::  sigma
+      INTEGER,     INTENT(in)    ::  niter
+      INTEGER,     INTENT(inout) ::  iflag
+
+!-----------------------------------------------------------------------
+!     Local Variables
+!
+!-----------------------------------------------------------------------
+      INTEGER :: ii
+      REAL(rprec)  :: F
+      REAL(rprec),PARAMETER  ::  A = 1.0
+      REAL(rprec),PARAMETER  ::  B = 100.0 
+!----------------------------------------------------------------------
+!     BEGIN SUBROUTINE
+!----------------------------------------------------------------------
+      IF (iflag < 0) RETURN
+      IF (iflag == 1) WRITE(iunit_out,'(A,2(2X,I3.3))') 'ROSENBROCK2D',1,5
+      IF (iflag == 1) WRITE(iunit_out,'(A)') 'TARGET  SIGMA  XVAL  A  B'
+      IF (niter >= 0) THEN
+         F = (A - xval)**2 + B*(yval - xval**2)**2
+         mtargets = mtargets + 1
+         targets(mtargets) = target
+         sigmas(mtargets)  = sigma
+         vals(mtargets)    = F
+         IF (iflag == 1) WRITE(iunit_out,'(5ES22.12E3)') target,sigma,vals(mtargets),A,B
+      ELSE
+         IF (sigma < bigno) THEN
+            mtargets = mtargets + 1
+            IF (niter == -2) target_dex(mtargets)=jtarget_Rosenbrock2D
+         END IF
+      END IF
+      RETURN
+!----------------------------------------------------------------------
+!     END SUBROUTINE
+!----------------------------------------------------------------------
+      END SUBROUTINE chisq_rosenbrock2d