java - 将值添加到数组的内容

Question

我有一个名为x=points的数组。该数组中有十个坐标(无论如何都是其中的 x 部分)。我想将 10 * c 值添加到数组中的每个点。另外，这是用java编写的。

我该怎么做？

for (int c = 0; c <= 9; c++) {
for(int k = 0; k <= 9; k++) {
        if (k%2 == 0) {
            xpoints[k] = (int) (20*Math.cos((k*3.14/5)+3*3.14/2)) +60;
            ypoints[k] = (int) (20*Math.sin((k*3.14/5)+3*3.14/2)) +60;
        } else if (k%2 == 1) {
            xpoints[k] = (int) (8*Math.cos((k*3.14/5)+3*3.14/2)) +60;
            ypoints[k] = (int) (8*Math.sin((k*3.14/5)+3*3.14/2)) +60;
            }
        }
    // This is where I am having trouble
    xpoints[] = xpoints + 5*c;
    g.fillPolygon(xpoints, ypoints, npoints);
}

Answer 1

// This is where I am having trouble
xpoints[] = xpoints + 5*c;

要更新数组中索引 i 处的值，请通过其索引访问它并重新分配更新的值:

xpoints[i] = xpoints[i] + 10 * c;

或更短:

xpoints[i] += 10 * c;

循环整个数组并更新每个值:

for (int i = 0; i < xpoints.length; i++) {
  xpoints[i] += 10 * c;
}

或者使用 Java 8 流:

xpoints = Arrays.stream(xpoints).map(xpoint -> xpoint + 10 * c).toArray();