199-201文件

guozhen3 · guozhen3 · commit 49154adee9f0 · 2021-08-05T11:28:53.000+08:00
diff --git a/README.md b/README.md
@@ -238,7 +238,7 @@ Python小例子 https://github.com/jackzhenguo/python-small-examples
 | 37 | [一行代码让 pip 安装加速 100 倍](md/176.md) | pip install | v1.0 | ⭐️⭐⭐ |
 
 
-### 综合小案例
+### 案例
 | 小例子 | 链接                    | 标签              | 版本          | 难度 |
 | ---- | ---------------------------------- | ---- | ---- | ---- |
 | 1   | [不用else和if实现计算器](md/60.md) | operator | V1.0 | ⭐️⭐️⭐️ |
@@ -268,9 +268,9 @@ Python小例子 https://github.com/jackzhenguo/python-small-examples
 | 25 | [寻找第n次出现位置](md/125.md) | enumerator | V1.0 | ⭐️⭐️⭐️ |
 | 26 | [找出所有重复元素](md/127.md) | calendar,datetime | V1.0 | ⭐️⭐️⭐️⭐️ |
 | 27 | [联合统计次数](md/128.md) | Counter | V1.0 | ⭐️⭐️⭐️⭐️⭐️ |
-
-
-
+| 28 | [求两点球面距离](md/199.md) | math asin | V1.0 | ⭐️⭐️⭐️⭐️⭐️ |
+| 29 | [获取文件编码](md/200.md) | chardet | V1.0 | ⭐️⭐️⭐️⭐️⭐️ |
+| 30 | [格式化json串](md/201.md) | json | V1.0 | ⭐️⭐️⭐️⭐️⭐️ |
 
 
 
@@ -374,4 +374,4 @@ Python关于数字的20个操作
 
 15 [更有用的数组操作](http://www.zglg.work/numpy/numpy-more-array-operations/)
 
-16 [生成随机数](http://www.zglg.work/numpy/numpy-generate-random-number/)
+16 [生成随机数](http://www.zglg.work/numpy/numpy-generate-random-number/)
diff --git a/md/199.md b/md/199.md
@@ -1,11 +1,29 @@
 
 ```markdown
 @author jackzhenguo
-@desc
+@desc 求两点球面距离
 @tag
 @version 
 @date 2020/04/06
 ```
-		     
+
+```python
+EARTH_RADIUS = 6378.137
+
+import math
+# 角度弧度计算公式
+def get_radian(degree):
+    return degree * 3.1415926 / 180.0
+# 根据经纬度计算两点之间的距离，得到的单位是 千米
+def get_distance(lat1,lng1,lat2,lng2):
+    radLat1 = get_radian(lat1)
+    radLat2 = get_radian(lat2)
+    a = radLat1 - radLat2 # 两点纬度差
+    b = get_radian(lng1) - get_radian(lng2); # 两点的经度差
+    s = 2 * math.asin(math.sqrt(math.pow(math.sin(a / 2), 2) + 
+                                math.cos(radLat1) * math.cos(radLat2) * math.pow(math.sin(b / 2), 2)));
+    s = s * EARTH_RADIUS
+    return s
+```		     
 
 <center>[上一个例子](198.md)    [下一个例子](200.md)</center>
diff --git a/md/200.md b/md/200.md
@@ -1,11 +1,29 @@
 
 ```markdown
 @author jackzhenguo
-@desc
+@desc 获取文件编码
 @tag
 @version 
 @date 2020/04/07
 ```
-		     
+
+```python
+import chardet
+from chardet import UniversalDetector
+
+def get_encoding(file):
+    with open(file, "rb") as f:
+        cs = chardet.detect(f.read())
+        return cs['encoding']
+    
+    detector = UniversalDetector()
+    with open(file, "rb") as f:
+        for line in f.readlines():
+            detector.feed(line)
+            if detector.done:
+                break
+        detector.close()
+    return detector.result
+```
 
 <center>[上一个例子](199.md)    [下一个例子](201.md)</center>
diff --git a/md/201.md b/md/201.md
@@ -1,11 +1,25 @@
 
 ```markdown
 @author jackzhenguo
-@desc
+@desc 格式化json串
 @tag
 @version 
 @date 2020/04/08
 ```
+```python
+import json
+
+
+def format_json(json_str: str):
+    dic = json.loads(json_str)
+
+    js = json.dumps(dic,
+                    sort_keys=True,
+                    ensure_ascii=False,
+                    indent=4,
+                    separators=(', ', ': '))
+    return js
+```
 		     
 
 <center>[上一个例子](200.md)    [下一个例子](202.md)</center>
