Attempting my first fortran 95 program, to solve quadratic eqn. Getting weird errors.
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Published on 2010-04-06T20:32:20Z
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2010/04/06
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So, I'm attempting my first program in Fortran, trying to solve quadratic eqn. I have double and triple checked my code and don't see anything wrong. I keep getting "Invalid character in name at (1)" and "Unclassifiable statement at (1)" at various locations. Any help would be greatly appreciated...
! This program solves quadratic equations
! of the form ax^2 + bx + c = 0.
! Record:
! Name: Date: Notes:
! Damon Robles 4/3/10 Original Code
PROGRAM quad_solv
IMPLICIT NONE
! Variables
REAL :: a, b, c
REAL :: discrim, root1, root2,
COMPLEX :: comp1, comp2
CHARACTER(len=1) :: correct
! Prompt user for coefficients.
WRITE(*,*) "This program solves quadratic equations "
WRITE(*,*) "of the form ax^2 + bx + c = 0. "
WRITE(*,*) "Please enter the coefficients a, b, and "
WRITE(*,*) "c, separated by commas:"
READ(*,*) a, b, c
WRITE(*,*) "Is this correct: a = ", a, " b = ", b
WRITE(*,*) " c = ", c, " [Y/N]? "
READ(*,*) correct
IF correct = N STOP
IF correct = Y THEN
! Definition
discrim = b**2 - 4*a*c
! Calculations
IF discrim > 0 THEN
root1 = (-b + sqrt(discrim))/(2*a)
root2 = (-b - sqrt(discrim))/(2*a)
WRITE(*,*) "This equation has two real roots. "
WRITE(*,*) "x1 = ", root1
WRITE(*,*) "x2 = ", root2
IF discrim = 0 THEN
root1 = -b/(2*a)
WRITE(*,*) "This equation has a double root. "
WRITE(*,*) "x1 = ", root1
IF discrim < 0 THEN
comp1 = (-b + sqrt(discrim))/(2*a)
comp2 = (-b - sqrt(discrim))/(2*a)
WRITE(*,*) "x1 = ", comp1
WRITE(*,*) "x2 = ", comp2
PROGRAM END quad_solv
Thanks in advance!
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