! 例題 6-7  行列の加工（平方根）［WHERE 文 ］
PROGRAM ex6_7

  IMPLICIT NONE
  INTEGER :: i, m = 0, n = 0
  REAL, ALLOCATABLE :: a( : , : )

  DO WHILE ( m <= 0 .OR. n <= 0 )
    PRINT *, 'Input array size m, n ( > 0 ) : '
    READ *, m, n
  END DO

  ALLOCATE ( a( 1 : m, 1 : n ) )

  PRINT '( 1X, A )', 'Input elements of a : '
  DO i = 1, m
    READ *, a( i, 1 : n )
  END DO

  WHERE ( a < 0.0E0 ) a = 0.0E0

  DO i = 1, m
    PRINT '( 10F8.5 )', SQRT( a( i, 1 : n ) )  
                      !  1行で表示するため10列以内と仮定してある
  END DO

END PROGRAM ex6_7