From d6fbe86e7a8c1bc389902c90c57ee7e80f5475b9 Mon Sep 17 00:00:00 2001
From: Joseph Redmon <pjreddie@gmail.com>
Date: Tue, 16 Dec 2014 19:40:05 +0000
Subject: [PATCH] updates?
---
src/utils.c | 55 +++++++++++++++++++++++++++++++++++++++----------------
1 files changed, 39 insertions(+), 16 deletions(-)
diff --git a/src/utils.c b/src/utils.c
index e100069..365faeb 100644
--- a/src/utils.c
+++ b/src/utils.c
@@ -30,19 +30,16 @@
void top_k(float *a, int n, int k, int *index)
{
int i,j;
- float thresh = FLT_MAX;
- for(i = 0; i < k; ++i){
- float max = -FLT_MAX;
- int max_i = -1;
- for(j = 0; j < n; ++j){
- float val = a[j];
- if(val > max && val < thresh){
- max = val;
- max_i = j;
+ for(j = 0; j < k; ++j) index[j] = 0;
+ for(i = 0; i < n; ++i){
+ int curr = i;
+ for(j = 0; j < k; ++j){
+ if(a[curr] > a[index[j]]){
+ int swap = curr;
+ curr = index[j];
+ index[j] = swap;
}
}
- index[i] = max_i;
- thresh = max;
}
}
@@ -260,14 +257,40 @@
return max_i;
}
+// From http://en.wikipedia.org/wiki/Box%E2%80%93Muller_transform
+#define TWO_PI 6.2831853071795864769252866
float rand_normal()
{
- int n = 12;
- int i;
- float sum= 0;
- for(i = 0; i < n; ++i) sum += (float)rand()/RAND_MAX;
- return sum-n/2.;
+ static int haveSpare = 0;
+ static double rand1, rand2;
+
+ if(haveSpare)
+ {
+ haveSpare = 0;
+ return sqrt(rand1) * sin(rand2);
+ }
+
+ haveSpare = 1;
+
+ rand1 = rand() / ((double) RAND_MAX);
+ if(rand1 < 1e-100) rand1 = 1e-100;
+ rand1 = -2 * log(rand1);
+ rand2 = (rand() / ((double) RAND_MAX)) * TWO_PI;
+
+ return sqrt(rand1) * cos(rand2);
}
+
+/*
+ float rand_normal()
+ {
+ int n = 12;
+ int i;
+ float sum= 0;
+ for(i = 0; i < n; ++i) sum += (float)rand()/RAND_MAX;
+ return sum-n/2.;
+ }
+ */
+
float rand_uniform()
{
return (float)rand()/RAND_MAX;
--
Gitblit v1.10.0