uniform_filter1d之nearest模式基于JAVA编程实现

 1     private static Double[] uniform_filter1d_double_fast(Double[] input, int size) {
 2         Double[] output = new Double[input.length];
 3         //https://github.com/scipy/scipy
 4         //‘nearest’ (a a a a | a b c d | d d d d)
 5         boolean more;
 6         int size1 = size/2;
 7         int size2 = size - size1 - 1;
 8         int maxLines = input.length - 1;
 9         int len = input.length;
10         int currentLine = 0;
11         double preWindowSum = 0.;
12         double preFirstValue = 0.;
13         boolean preInitialized = false;
14         do {
15             Double tmp = 0.;
16             if (!preInitialized) {
17                 int start = 0;
18                 preFirstValue = input[start];
19                 for (int i = 0; i < size1; i++) {
20                     tmp = p_double_add(tmp, input[start]);
21                 }
22                 tmp = p_double_add(tmp, input[currentLine]);
23                 for (int i = 0; i < size2; i++) {
24                     tmp = p_double_add(tmp, input[currentLine+i+1]);
25                 }
26             } else {
27                 preWindowSum = p_double_subtract(preWindowSum, preFirstValue);
28                 if (currentLine > size1) {
29                     preFirstValue = input[currentLine-size1];
30                 }
31                 if (currentLine+size2 <= maxLines) {
32                     tmp = p_double_add(preWindowSum, input[currentLine+size2]);
33                 } else {
34                     tmp = p_double_add(tmp, input[maxLines]);
35                 }
36             }
37             preWindowSum = tmp;
38             if (!preInitialized) {
39                 preInitialized = true;
40             }
41             output[currentLine] = p_double_divide(tmp , size);
42             currentLine++;
43             more = currentLine < len;
44         } while (more);
45         return output;
46     }

以上为分析scipy库中的c++代码后所写。