Modified systemtest test_estimate_r2eff_err_methods, to check all Jacobian methods are correctly implemented.
task #7822(https://gna.org/task/index.php?7822): Implement user function to estimate R2eff and associated errors for exponential curve fitting.
Authored by: tlinnet 2014-08-29
Parent: [r25455]
Child: [r25457]
