Built-in function_Cross analysis and instructions

Built-in function_Cross analysis and instructions

The _Cross function in the global function array in the API documentation is used to calculate the cross state of two pointer lines

• The function implements code similar to the following:

  It's important to note thatarr1It is defined as a fast-track indicator array.arr2When defined as a slow-line indicator array,_CrossThe function returns a positive value, i.e. according to the document.正数为上穿周期, 负数表示下穿的周期, 0指当前价格一样I know, right now.arr1Get up there.arr2It's been n cycles, at which point the fast line crosses the slow line to represent the golden fork. The same._CrossIf the function returns a negative number, it is a dead fork.

  If definedarr1For the slow-line indicator array,arr2For the fast-line indicator array, the opposite is true._CrossThe function returns a positive value for the dead fork._CrossThe function returns a negative value representing the gold fork.

// 返回上穿的周期数，正数为上穿周数，负数表示下穿的周数，0指当前价格一样
$.Cross = function(arr1, arr2) {            // 参数个数为2个，从参数名可以看出，这两个参数应该都是数组类型，数组就
                                            // 好比是在X轴为数组索引值，Y轴为指标值的坐标系中的线段，该函数就是判断两条线的 交叉情况 
    if (arr1.length !== arr2.length) {      // 首先要判断比较的两个数组长度是否相等
        throw "array length not equal";     // 如果不相等抛出错误，对于不相等的指标线无法判断相交
    }
    var n = 0;                              // 声明变量n用来记录交叉状态，初始0，未相交 
    for (var i = arr1.length-1; i >= 0; i--) {      // 遍历数组arr1，遍历顺序为从最后一个元素向前遍历
        if (typeof(arr1[i]) !== 'number' || typeof(arr2[i]) !== 'number') { // 当arr1或者arr2任何一个数组为非数值类型（即无效指标）时，跳出遍历循环
            break;                                  // 跳出循环
        }
        if (arr1[i] < arr2[i]) {                    // 如果arr1小于arr2则n--，会记录开始时arr1、arr2的相对状态，（即开始时n会根据arr1[i]、arr2[i]相对大小自行调整，一旦出现另一种和n状态相反的arr1[i]、arr2[i]大小关系，即发生了两条线交叉。）
            if (n > 0) {
                break;
            }
            n--;
        } else if (arr1[i] > arr2[i]) {             // 如果arr1大于arr2则n++
            if (n < 0) {
                break;
            }
            n++;
        } else {                                    // arr1[i] == arr2[i]，则立即跳出
            break;
        }
    }
    return n;                                       // 返回n值，代表已经交叉了多少周期，0即指标值相等
};

• So we simulate a set of data to be fed into this parameter and see what happens.

var arr1 = [1,2,3,4,5,6,8,8,9]     // 快线指标
var arr2 = [2,3,4,5,6,7,7,7,7]     // 慢线指标
function main(){
    Log("_Cross(arr1, arr2) : ", _Cross(arr1, arr2))
    Log("_Cross(arr2, arr1) : ", _Cross(arr2, arr1))
}

You can see that the result is 3, 3, 3.

As can be seen in the diagram, the position of the intersection occurs before the three K-line columns.