From bf42840d814e46096ab9b3727d113ddea2335966 Mon Sep 17 00:00:00 2001
From: "W. Trevor King" <wking@drexel.edu>
Date: Sat, 6 Nov 2010 08:27:44 -0700
Subject: [PATCH] Standardize max step calculation and fit-parameter
 requirements in pysawsim.test.

---
 pysawsim/test/bell_rate.py     | 2 +-
 pysawsim/test/constant_rate.py | 9 +++++----
 2 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/pysawsim/test/bell_rate.py b/pysawsim/test/bell_rate.py
index 1911900..f542433 100644
--- a/pysawsim/test/bell_rate.py
+++ b/pysawsim/test/bell_rate.py
@@ -179,7 +179,7 @@ def bell_rate(sawsim_runner, num_domains=1, unfolding_rate=1,
     sim_alpha = params[0]
     sim_rho = abs(params[1])
     for s,t,n in [(sim_alpha, alpha, 'alpha'), (sim_rho, rho, 'rho')]:
-        assert (s - t)/w < 3, (
+        assert abs(s - t)/w < 3, (
             'simulation %s = %g != %g = %s (bin width = %g)' % (n,s,t,n,w))
     return sim.residual(theory)
 
diff --git a/pysawsim/test/constant_rate.py b/pysawsim/test/constant_rate.py
index 63fd4f7..c71bdf5 100644
--- a/pysawsim/test/constant_rate.py
+++ b/pysawsim/test/constant_rate.py
@@ -112,7 +112,7 @@ def constant_rate(sawsim_runner, num_domains=1, unfolding_rate=1,
                   spring_constant=1, velocity=1, N=100):
     loading_rate = float(spring_constant * velocity)
     tau = loading_rate / unfolding_rate
-    w = 0.1 * tau  # calculate bin width (in force)
+    w = 0.2 * tau  # calculate bin width (in force)
     A = w*num_domains*N / tau
     theory = Histogram()
     # A exp(-x/tau) = 0.001
@@ -124,8 +124,8 @@ def constant_rate(sawsim_runner, num_domains=1, unfolding_rate=1,
         theory.bin_centers, [tau])
     theory.analyze()
 
-    max_time_step = tau/10.0
-    max_force_step = loading_rate * max_time_step
+    max_force_step = w/10.0
+    max_time_step = max_force_step / loading_rate
     param_string = (
         '-d %(max_time_step)g -F %(max_force_step)g -v %(velocity)g '
         '-s cantilever,hooke,%(spring_constant)g -N1 '
@@ -139,7 +139,8 @@ def constant_rate(sawsim_runner, num_domains=1, unfolding_rate=1,
     params = e.fit()
     sim_tau = abs(params[0])
     for s,t,n in [(sim_tau, tau, 'tau')]:
-        assert (s - t)/t < 0.1, 'simulation %s = %g != %g = %s' % (n,s,t,n)
+        assert abs(s - t)/w < 3, (
+            'simulation %s = %g != %g = %s (bin width = %g)' % (n,s,t,n,w))
     return sim.residual(theory)
 
 
-- 
2.26.2