calc exp(F/kT) instead of F for each window

This commit is contained in:
Daniel Bauer
2018-10-17 10:21:19 +02:00
parent 40bb99a612
commit b064ecea6d

View File

@@ -64,15 +64,14 @@ fn calc_bin_probability(bin: usize, ds: &Dataset, F: &[f64]) -> f64 {
// estimate the bias offset F of the histogram based on given probabilities // estimate the bias offset F of the histogram based on given probabilities
// This evaluates the second WHAM equation for each window // This evaluates the second WHAM equation for each window
fn calc_window_F(window: usize, ds: &Dataset, P: &[f64]) -> f64 { fn calc_window_F(window: usize, ds: &Dataset, P: &[f64]) -> f64 {
let bf_sum: f64 = (0..ds.num_bins).zip(P.iter()) // zip bins and P (0..ds.num_bins).zip(P.iter()) // zip bins and P
.filter_map(|count_and_prob: (usize, &f64)| { .filter_map(|bin_and_prob: (usize, &f64)| {
if count_and_prob.1 == &0.0 { // skip zeros for speed if bin_and_prob.1 == &0.0 { // skip zeros for speed
None None
} else { } else {
Some(count_and_prob.1 * (-(-ds.kT*ds.calc_bias(count_and_prob.0, window).ln()) / ds.kT).exp()) Some(bin_and_prob.1 * ds.calc_bias(bin_and_prob.0, window))
} }
}).sum(); }).sum()
-ds.kT * bf_sum.ln()
} }
// One full WHAM iteration includes calculation of new probabilities P and // One full WHAM iteration includes calculation of new probabilities P and
@@ -231,11 +230,18 @@ fn dump_state(ds: &Dataset, F: &[f64], F_prev: &[f64], P: &[f64], A: &[f64]) {
} }
} }
#[cfg(test)] #[cfg(test)]
mod tests { mod tests {
use super::histogram::{Dataset,Histogram}; use super::histogram::{Dataset,Histogram};
use std::f64; use std::f64;
macro_rules! assert_delta {
($x:expr, $y:expr, $d:expr) => {
assert!(($x-$y).abs() < $d, "{} != {}", $x, $y)
}
}
#[test] #[test]
fn is_converged() { fn is_converged() {
let new = vec![1.0,1.0]; let new = vec![1.0,1.0];
@@ -262,14 +268,13 @@ mod tests {
} }
#[test] #[test]
#[ignore]
fn calc_bias_offset() { fn calc_bias_offset() {
let ds = create_test_ds(); let ds = create_test_ds();
let probability = vec!(0.959, 0.331, 0.656, 46.750); let probability = vec!(0.959, 0.331, 0.656, 46.750);
let expected = vec!(0.596, -0.250); let expected = vec!(0.786289183, 1.10629119);
for window in 0..ds.num_windows { for window in 0..ds.num_windows {
let F = super::calc_window_F(window, &ds, &probability); let F = super::calc_window_F(window, &ds, &probability);
assert_near(expected[window], F, 0.001); assert_delta!(expected[window], F, 0.0000001);
} }
} }