python - Appending modified object to list in for loop -- only last modification is stored -

-

i created function goes through loop, creates variables, , appends them in list.

    def function(self,record):         temp_list_records=[]         #depends number of x, got 10, 100,1000,10000 loops         loops=int(math.pow(10,x_range))         digits="%0"+str(x_range)+"d"          #then create records , add mysql data query         x in range (0,loops):              end_of_number=digits%x             record.dn=dn_number+str(end_of_number)             record.gn=gn_number+str(end_of_number)              temp_list_records.append(record)          return temp_list_records

explanation: pass object called record has 2 properties, dn , gn. these properties have structure: 0000213123xx, xx two-digit number. need generate values xx in range between 00 , 99, properties be: 000021312300, 000021312301,... every time append list record, record dn , gn change in range. explain later, during loop, numbers found, once loop finished, objects in list become last 1 found.

then values returned in list are: 

 000021312399 000021312399 000021312399 000021312399 000021312399 000021312399 000021312399 000021312399

but, if put print inside loop:

def function(self,record):         temp_list_records=[]         #depends number of x, got 10, 100,1000,10000 loops         loops=int(math.pow(10,x_range))         digits="%0"+str(x_range)+"d"          #then create records , add mysql data query         count=0         x in range (0,loops):              end_of_number=digits%x             record.dn=dn_number+str(end_of_number)             record.gn=gn_number+str(end_of_number)              temp_list_records.append(record)             print temp_list_records[count].dn             count+=1          return temp_list_records

the result of prints are:

 000021312300 000021312301 000021312302 000021312303 000021312304 000021312305 000021312306 000021312307 ...

can explain me why? how solve this?

as @martineau has commented, problem you've appended temp_list_records bunch of references same object, record. hence, when loop finished, contents of list same.

this can fixed one-line change code. have re-initialize record inside each iteration of loop (so each loop has separate instance):

def function(self,record):     temp_list_records=[]     #depends number of x, got 10, 100,1000,10000 loops     loops=int(math.pow(10,x_range))     digits="%0"+str(x_range)+"d"      #then create records , add mysql data query     x in range (0,loops):          record = get_new_record()  # change.          end_of_number=digits%x         record.dn=dn_number+str(end_of_number)         record.gn=gn_number+str(end_of_number)          temp_list_records.append(record)      return temp_list_records

of course, replace get_new_record call appropriate class.


Comments

Post a Comment

Popular posts from this blog

c++ - No viable overloaded operator for references a map -

-
i trying use map can make tag names reference number. when try , use it, in code error (6 in total every time reference map): src/main.cpp:25:45: error: no viable overloaded operator[] type 'std::map<std::string, std::string>' const char* idcs = node.child_value(tagmap[3]); this code: #include "pugi/pugixml.hpp" #include <iostream> #include <string> #include <map> int main() { pugi::xml_document doca, docb; std::map<std::string, pugi::xml_node> mapa, mapb; std::map<std::string, std::string> tagmap {{"1", "data"}, {"2", "entry"}, {"3", "id"}, {"4", "content"}}; if (!doca.load_file("a.xml") || !docb.load_file("b.xml")) { std::cout << "can't find input files"; return 1; } (auto& node: doca.child(tagmap[1]).children(tagmap[2])) { co
Read more

java - Custom OutputStreamAppender not run: LOGBACK: No context given for <MYAPPENDER> -

-
i wish write custom appender on basis of outputstreamappender . wrote following class package tests; import java.io.ioexception; import java.io.outputstream; import ch.qos.logback.core.outputstreamappender; public class myappender<e> extends outputstreamappender<e> { public myappender() { system.out.println("myappender created"); setoutputstream(new outputstream() { @override public void write(int b) throws ioexception { throw new unsupportedoperationexception(); } }); } } then wrote following runner: package tests; import org.slf4j.loggerfactory; import ch.qos.logback.classic.logger; public class runner { private static final logger log = (logger) loggerfactory.getlogger(runner.class); public static void main(string[] args) { //log.addappender(new myappender<iloggingevent>()); log.info("hello world"); } } finall
Read more

java - Cannot secure connection using TLS -

-
i'm trying establish secure socket connection between java client applet (built jdk 1.7.0_75-b13) , vc++ server application. as test vehicle, used vc++ client/server sample found in msdn forums, modified use schannel , able establish socket using cipher suite tls_rsa_with_aes_128_cbc_sha. works of tls 1.0/1.1/1.2. when try opening socket java applet same server application, connection rejected server reporting following: tls 1.0 acceptsecuritycontext failed: 0x80090327 tls 1.1 acceptsecuritycontext failed: 0x80090331 tls 1.2 acceptsecuritycontext failed: 0x80090331 this java code used create socket: debugprint("setting secure connection"); sslsocketfactory sslsocketfactory = (sslsocketfactory) sslsocketfactory.getdefault(); sslsocket sslsocket = (sslsocket) sslsocketfactory.createsocket("127.0.0.1", socketnumber); debugprint("starting handshake"); sslsocket.settcpnodelay(true); sslsocket.setsolinger(false, 0); sslsocket.s
Read more