我在使用public class WSAdapter {
/*@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}*/
public class SendPostsRequest extends AsyncTask<String, String, String> {
TextView postsSect;
// Add a pre-execute thing
HttpURLConnection urlConnection;
private WeakReference<Activity> mPostReference;
/*public SendPostsRequest(Activity activity){
mPostReference = new WeakReference<Activity>(activity);
}*/
@Override
protected String doInBackground(String... params) {
StringBuilder result = new StringBuilder();
try {
urlConnection = (HttpURLConnection) new URL(params[0]).openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.connect();
InputStream in = new BufferedInputStream(urlConnection.getInputStream());
BufferedReader reader = new BufferedReader(new InputStreamReader(in));
String line;
while ((line = reader.readLine()) != null) {
result.append(line);
}
}catch( Exception e) {
e.printStackTrace();
}
/*finally {
urlConnection.disconnect();
}*/
return result.toString();
}
@Override
protected void onPostExecute(String result) {
// expecting a response code fro my server upon receiving the POST data
Log.e("TAG", result);
Posts.PostsDetails postsHelper = new Posts().new PostsDetails();
// For posts
try {
JSONArray pJObjArray = new JSONArray(result);
// algorithm for parsing the JSONArray from the Django REST API
for (int i = 0; i < pJObjArray.length(); i++) {
// puts the current iterated JSON object from the array to another temporary object
JSONObject pJObj_data = pJObjArray.getJSONObject(i);
// inputs necesarry elements to the ListPosts function
postsHelper.setPost(pJObj_data.getInt("id"), pJObj_data.getString("post_title"), pJObj_data.getString("post_content"));
}
} catch (JSONException e) {
//Toast.makeText(JSonActivity.this, e.toString(), Toast.LENGTH_LONG).show();
Log.d("Json","Exception = "+e.toString());
}
postsHelper.ListPosts();
}
}
}
时遇到问题。我做到了：
sin但是，当我在计算器中键入include Math
puts sin(5) # => -0.9589242746631385
时，它将输出sin(5)。同样，我尝试使用方程pi = x * sin（180 / x）计算PI的值，尽管我在计算器上得到了PI的值，但还是遇到了问题。
0.087155742谢谢任何人的帮助。
答案 0 :(得分：2)
您的方程式用于计算角度的正弦度数。
大多数（也许是所有）计算机语言sin（）函数期望角度为弧度。
不幸的是，您需要为pi设置一个值，以便将其从一个转换为另一个。因此，除非找到渐进式实施，否则您将陷入困境。
这是因为您的公式来自弧度和度之间的2×π/ 360或π/ 180转换。