brackets - Python - what is this syntax? my_2d_list[0:20,1] -

-

To find out what's inside the bracket, a difficult time with an interpreter is Google or nude. The reference is the code: matplotlib.mlab import from mlabPCA mlab_pca = mlabPCA (all_samples.T.) In the form of PCA ('in terms of measurement axes' from PC axis '\' standard Increased deviation: \ n ', \ mlab_pca.Wt) plt.plot (mlab_pca.Y [0: 20,0], mlab_pca.Y [0: 20,1],' o ', markers = 7, \ color =' Blue ',' alpha = 0.5, label = 'class1') plt.plot (mlab_pca.Y [20: 40,0], mlab_pca.Y [20: 40,1], '^', marker size = 7, \ Color = 'red', alpha = 0.5, label = 'class2') plt.xlabel ('x_values') plt.ylabel ('y_values') plt.xlim ([- 4,4]) plt. Ylim ([- 4,4]) plt.legend () plt.title ('matplotlib.mlab.PCA (to be replaced with class labels') plt.show ()

I have Tried to create a small 2D array 

  a = [[1,2], [1,2], [1,2], [1,2], [1] , 2]]   
 and evaluation  
  a [0: 2.0]   
 But he did something to me Not even thank you!  
 The code taken from the "using the PCA (class) matplotlib.mlab library" section.   
  After "text" itemprop = "text"> 
 Indigenous Python Lists (which you are creating for  a ) Do not support indexing or skiing, at least in the way you are doing this, to use index and slice, you can use syntax, because you are already using it:  
     
  1.  To use index and slice  
       
    1.   
        np a = np.array ([[1,2], Samples as [1,2], [1,2], [1,2], [1,2] Importing]] [0: 2, 0] # Returns array ([1, 1])   
         
      1.  Your original python list with a different syntax Log in.   
         This method does not really allow you to split the way you are using it, but, you can:  a [0 ] [1]  to access 0, 1 element correctly with  a [0, 1]  list. But again, a piece of action ( one [0: 2] [0]  will produce some unwanted results).  
         It seems that you may have syntax options based on some, if so, then use this great reference guide to reduce the infection:

Comments

Post a Comment

Popular posts from this blog

php - PDO bindParam() fatal error -

-
I am trying to learn PDO, now I have written this small code, but it gives me a serious error: < P> Fatal error: Call a member function at a non-object dot () ... $ con = new mysqli ("127.0.0.1", "root", "", "csvdangercheck"); $ Query = $ con- & gt; ("Id,` var1`, `var2`) values ​​(" id,: var1,: var2) ";); $ query- & gt; bypass pattern (': id', $ id); $ query- & gt; BindParam (': var1', $ VAL1); $ Query- & gt; bindParam (': var2', $ val2); $ Query-> Executed (); I Trying to use print_r ($ con-> errorInfo ()) but Fatal error: Undefined method mysqli :: errorInfo ( ) ... can someone tell me what am I missing? Flaffeh said, you have PDO Missing Mysqy, try it: $ con = new PDO ('mysql: host = 127.0.0.1; dbname = csvdangercheck', 'root', '');
Read more

logging - How can I log both the Request.InputStream and Response.OutputStream traffic in my ASP.NET MVC3 Application for specific Actions? -

-
For a specific set of tasks, I need to log in to the incoming request inputstream as well as outgoing response. is. I am using an ActionFilterAttribute for this and overriding the OnActionExecuted and OnResultExecuted methods. So I'm starting with this idea ... Public category ActionLoggerAttribute: ActionFilterArrbit {Public Override Zero On-Offed Execution (ActionActioned Contact Filter Filter) {base.OnActionAxecuted (FilterContext); HttpRequestBase request = filterContext.HttpContext.Request; // TODO: Log the request. InputStream} Public Override Zero OnResultExecuted (ResultExecutedContext FilterContext) {base.OnResultExecuted (filterContext); HTTPRPSPointBase Response = FilterContacts Hpptex response; // TODO: Log on Response.OutputStream}} Ideally I'll hook it up with enterprise library logging because I'm already using it for error logging. Am I reaching the input and output stream at the right time? Can I easily use the Enterprise Library to log i
Read more

java - Why my included JSP file won't get processed correctly? -

-
I am trying to create Java web framework (and learning), and on the basis of 'Code Generator In the process of making the material view of the database in the process of development, I stumbled into a difficulty, which I do not know how to solve it. First of all, I want the following index.jsp : & lt; Body & gt; Use all pages to be created. & Lt;% @ include file = "header.jsp"% & gt; & Lt; Hours / & gt; & Lt;% @ included file = "body.jsp"%> & Lt; Hours / & gt; & Lt;% @ include file = "footer.jsp"% & gt; & Lt; / Body & gt; And, in body.jsp , I should have it like this: & lt; Jsp: include page = "$ {Application_modul}"%> Where application_modul is an attribute defined in its controller: request.setAttribute ("application_modul", "USER_ACCOUNT \\ ' View_user_account.jsp "); This file can be found properly, but the processed JSP does
Read more