Implicit conversion

Similar Questions

• CVI2013: WARNING: implicit conversion changes signedness: "long" to "int".

  What is Clang was trying to say with this warning?

  int f( void )
  {
    int i1 = 4;
  
    int i2 = 1l << ( i1 - 1 );
    //       ^^  warning: implicit conversion changes signedness: 'long' to 'int' [-Wsign-conversion]
  
    return i2;
  }
  

  Hello CVI - User!

  The explanation is quite technical...

  The result type of the expression of SHIFT is "signed for a long time." The target type of the initialization is "signed int". Clang injects an implicit "signed long" conversion to "signed int" and check the different properties of the conversion.

  In particular, clang tests if the sign of the value can change during the conversion. For this test, clang calculates the range of 'values' of the source 1 L< (i1="" -="" 1)'="" and="" the="" "value="" range"="" of="" the="" target="" 'int="" i2'.="" the="" warning="" indicates="" that="" the="" signs="" of="" the="" source="" and="" target="" ranges="" do="" not="">

  The range of values of the source depends on the expression 1 L< (i1="" -="" 1)'="" and="" here="" clang="" is="" applying="" a="" special="">

      [excerpt from GetExprRange in the clang 2.9 source code]
  
      // Left shift gets black-listed based on a judgement call.
      // ...except that we want to treat '1 << (blah)' as logically
      // positive.  It's an important idiom.
  

  Therefore the range of values of source is: wide, 32-bit positive.

  The range of values of the target depends on the type of "i2" and that's the range of default values for "signed int": 32 - bit wide, positive or negative.

  In other words: 1 L< (i1="" -="" 1)'="" is="" considered="" positive="" (unsigned)="" and="" it="" is="" converted="" to="" a="" signed="">

  Note that this is really a special case and that you do not get the warning for other values:

    int i2 = 2l << ( i1 - 1 ); //no warning
  

  Unfortunately, I can not explain why clang didn't just compare the source and target types, it calculates the ranges of values and why 1< (blah)'="" is="" treated="" specially.="" i="" don't="">

  Peter

• implicit conversion to sql

  Hi guys,.
  
  I have a question on how the oracle is posting implicit conversion in the following cases.
  
  I have a table: table1 with two columns: a number (10), b varchar2 (10). Both are indexed unique.
  
  
  If I have a SQL like this:

  select * from table1 where a = '99'

  the implicit conversion is performed on '99' and the final SQL will be something like:

  select * from table1 where a = to_number ('99')

  the same thing will happen with 'aaa' and I get an error. Please note that represents the column and the index will be used.
  
  If I have a sql like:

  select * from table1 where b = 99

  Note that b is the varchar2 column.
  the implicit conversion will be done on the column and the index will not be used

  select * from table1 where to_number (b) = 99

  THEN, forgetting for a moment that it is not OK to allow an implicit conversion, what are the rules that apply here? If the number, the conversion will be made on the value and varchar conversion will be performed on the column? What else?
  
  
  Thank you

  http://docs.Oracle.com/CD/E11882_01/server.112/e26088/sql_elements002.htm#SQLRF51047

• If an implicit conversion takes place

  Hi all
  
  I have two queries tell
  
  SQL > SELECT * FROM EMP WHERE HIREDATE BETWEEN February 20, 81 'AND February 20, 82';
  
  EMPNO, ENAME, JOB HIREDATE DEPTNO COMM SAL MGR
  ----- ---------- --------- ---------- --------- ---------- ---------- ----------
  7499 ALLEN 7698 1600 20 FEBRUARY SALESMAN 81 300 30
  7521 WARD 7698 1250 22 FEBRUARY SALESMAN 81 500 30
  7566 JONES MANAGER 7839 2975 2 APRIL 81 20
  7654 MARTIN 7698 28 - SEP - 81 1250 1400 30 SALESMAN
  7698 BLAKE MANAGER 7839 2850 MAY 1, 81 30
  7782 10 removed MANAGER 7839 2450 June 9 81 10
  7839 10 deleted PRESIDENT November 17, 81 5000 10
  7844 TURNER 7698 08 - SEP - 81 1500 0 30 SALESMAN
  7900 7698 DECEMBER 3, CLERK JAMES 81 950 30
  7902 7566 3000 3 DECEMBER ANALYST FORD 81 20
  7934 10 deleted CLERK 7782 1300 January 23 82 10
  
  AND
  
  SQL > select' 17-SEP-2010 + 1 double;
  
  ERROR on line 1:
  ORA-01722: invalid number
  
  now in the first case, I spent a string and that turned into a date
  but in the second case, I try to add a day to this date it is not be converted in the second case.
  
  When in fact the implicit conversion is done.
  
  Thank you and best regards,
  Sri ram.

  Probably below may be the reason.
  In the first query you asked oracle to match the hiring date between two dates. Oracle implicitley equal strings depending on the hiring date data type.
  But in the 2nd query you specify a string in your oracle query does not include what format to convert the string.

• The implicit conversion of "char to number" or "number of char".

  CREATE TABLE test_table
  (
  NUM NUMBER,
  VCH VARCHAR2 (10)
  );
  
  INSERT INTO table_test VALUES
  (1, '1') ;
  
  INSERT INTO table_test VALUES
  (2, '2') ;
  
  SELECT * FROM test_table WHERE vch = 1;
  
  When comparing, what type of data is converted into what - all vch values are converted in number or 1 is converted to char '1'?

  Hello

  Welcome to the forum!

  The answer to your question is in the predicate explain plan section:

  filter predicates: to_number ("VCH") = 1

  Best regards
  Nikolai

• Error when the concatenation of CLOB using conversion implicit to_char

  Hello
  
  Please look at the code below (Oracle 11.1.0.7.0):
  

  DECLARE
    c CLOB;
  BEGIN
    FOR i IN 1..10
    LOOP
      -- Please uncomment ONE of the lines below
      c := c ||  LPAD('x', 8000, 'z') || i; -- raises error ora-06502
      --c := c || (LPAD('x', 8000, 'z') || i);  -- works
      --c := c ||  LPAD('x', 8000, 'z') || to_char(i);  -- works
    END LOOP;
  END;

  OK, making use of implicit type conversion may not be the best thing to do, but just out of curiosity, is there any explanation for this error to occur?
  
  It seems that, when an implicit conversion is involved without the help of hooks, Oracle tries to convert all in varchar2 before concatenate in the clob, which causes the error.
  
  Thank you
  Luis

  Hello
  >
  # 6.1, we have a clob and a varchar2, as in #2; Why Oracle has decided to convert the clob in varchar2 as you say, and not vice versa as in #3?
  >

  # 5, we have clob and number at the beginning. In order to evaluate the expression oracle requires that two variables was of the same type.
  As the implicit conversion there is no number-> clob
  but there are several-> varchar2 and clob-> varchar2 oracle choose this one.

• A design of query for the conversion of time difference in days, hours, Minutes

  Hi all

  A design of query for the conversion of time difference of time in number of days remaining remaining hours minutes and rest in seconds. Made this one till now. Please suggest for all modifications, until now, it seems to work very well, kindly highlight for any anomaly.

  WITH DATA (startDAte, EndDate, Datediff) AS (SELECT to_date ('2015-10-01 10:00:59 ',' yyyy-mm-dd hh24:mi:ss'), to_date ('2015-20-01 03:00:49 ',' yyyy-mm-dd hh24:mi:ss'), to_date('2015-10-01 10:00','yyyy-dd-mm hh24:mi:ss')-to_date('2015-20-01 03:00','yyyy-dd-mm hh24:mi:ss') FROM dual)

  UNION ALL SELECT to_date ('2015-10-01 10:00:39 ',' yyyy-mm-dd hh24:mi:ss'), to_date ('2015-20-01 03:00:40 ',' yyyy-mm-dd hh24:mi:ss'), to_date('2015-10-01 10:00','yyyy-dd-mm hh24:mi:ss')-to_date('2015-20-01 03:00','yyyy-dd-mm hh24:mi:ss') FROM dual

  UNION ALL SELECT to_date ('2015-11-01 10:30:45 ',' yyyy-mm-dd hh24:mi:ss'), to_date ('2015-11-01 11:00:50 ',' yyyy-mm-dd hh24:mi:ss'), to_date('2015-11-01 10:30','yyyy-dd-mm hh24:mi:ss')-to_date ('2015-11-01 11:00 ',' yyyy-mm-dd hh24:mi:ss') FROM dual

  UNION ALL SELECT to_date ('2015-11-01 09:00:50 ',' yyyy-mm-dd hh24:mi:ss'), to_date ('2015-11-01 10:00:59 ',' yyyy-mm-dd hh24:mi:ss'), to_date('2015-11-01 09:00','yyyy-dd-mm hh24:mi:ss')-to_date ('2015-11-01 10:00 ',' yyyy-mm-dd hh24:mi:ss') FROM dual

  UNION ALL SELECT to_date ('2015-11-01 08:30:49 ',' yyyy-mm-dd hh24:mi:ss'), to_date ('2015-11-01 09:30:59 ',' yyyy-mm-dd hh24:mi:ss'), to_date('2015-11-01 08:30','yyyy-dd-mm hh24:mi:ss')-to_date('2015-11-01 09:30','yyyy-dd-mm hh24:mi:ss') FROM dual

  )

  Select

  trunc ((EndDate-StartDate)) days.

  trunc (((enddate-startdate)-to_number (trunc ((enddate-startdate))) * 24) hours)

  trunc (to_number (((enddate-startdate)-to_number (trunc ((enddate-startdate))) * 24-trunc (((enddate-startdate)-to_number (trunc ((enddate-startdate))) * 24)) * 60) Minutes,))

  (to_number (((enddate-startdate)-to_number (trunc ((enddate-startdate))) * 24-trunc (((enddate-startdate)-to_number (trunc ((enddate-startdate))) * 24)) * 60 - trunc (to_number (((enddate-startdate)-to_number (trunc ((enddate-startdate))) * 24-trunc (((enddate-startdate)-to_number (trunc ((enddate-startdate))) * 24)) * 60)) * 60 seconds))))

  data;

  Thanks for the answers in advance.

  AHA!

  TO_TIMESTAMP expects a string as input, so it first makes an implicit conversion from DATE to a string, in the format of NSL_DATE_FORMAT.

  To convert the TIMESTAMP DATE independently NLS_DATE_FORMAT, use

  CAST ( AS TIMESTAMP)

• Char to Varchar type Conversion

  Hi gurus.
  
  I have a simple question.
  
  In my ETL mapping, I have a table of the source columns are char (20) and in the target table, the columns are varchar2 (20).
  
  When I run a validation in the ETL mapping, I got a warning message (VLD-1001) regarding the conversion implicitly.
  
  The question is:
  
  How to make this conversion of char varchar2 using an expression?
  
  Thanks in advance.

  Bruno,
  CAST is an Oracle SQL standard function: http://download.oracle.com/docs/cd/B19306_01/server.102/b14200/functions016.htm#i1269136

  So, to use in your map, you would add an expression object between your source and target tables. Bind your tank (20) source field in the membership of the expression group and create a field of type varchar2 external group (20).

  Then, in the attributes property for this pane outgroup fieldset property of "Expression".
  CAST (ingrp1.sourcefield_name as varchar2 (20)).

  then connect this field outgrp above your target table. That is now for an explicit cast to the source field to varchar2 (20) in select statements and fusion in your generated code and thus get rid of the warning raised by your ongoing implicit conversion.

  See you soon,.
  Mike

• On a more specific class or the variant

  Which of these methods is preferred for the update of GUI? Any show hit with for Variant?

  

  Out of curiosity and for a fan of Top Gear (real BBC version, not lame History Channel knock-off) colleague here are a few quick comparative data:

  

  Another case where fear of stress points leads to evil.  Put in explicit conversion of the type variant slows things down a bit more than the specific class that I suspect (but didn't).  However, my strategy to connect life with the point red and right value help considerably, as the implicit conversion is as fast as a bound property node (laziness country off, yes!).  Inhabitants of smoke just PNs, but we knew that and I just wanted to see with my own eyes.

• cwimaq vs imaqdx image data structure

  I'm using VB.net (2005) in a simple firewire camera snap and save the application.  I used before CWIMAQ com objects in VB6 without problem (using the WriteImage function).  I made a vast machine vision work in VB6 with the CWIMAQ, so I know that those tools, my trouble is now I'm trying to port to VB.net.

  Currently I can not examples of dotnet component image snap-in to work with the CWIMAQ objects in dotnet.  I tried the examples included with the NI Vision acquisition tools and have had success with the c# examples for imaqdx, not CWIMAQ. The port inherited examples from VB6 to .net, however, there are some usability issues with the structure of COM I'm not smart enough to defeat in .net.

  Here's my problem, and maybe there is a simple solution.  I need to save the image and cannot for the life of find me the imaqdx method that was similar to the cwimaq.writeimage function.  I have the snap-snap-imaqdx working in vb.net, I tried to use the CWIMAQ.writeimage, but of course, I get an error of "implicit conversion" between the CWIMAQ and the data structures imaqdx image. I can get the imaqdx.image as image system.forms.drawing?

  Y at - it an easy way to save an image using the tools of imaqdx in VB.net-similar to the way in which we used CWIMAQ. WriteImage?  Can someone point me to an example or a net which shows?

  Thank you

  James

  Hi James,

  The write functions are methods of the image of the Vision. For example, to save the image in png, you would call

  imageViewer1.Image.WritePngFile

  Our examples of languages of text can be accessed from the Start Menu (programs > National Instruments > Vision > text basic example)

  Hope this helps,

  -Christophe

• How he handles the labview to more generic class

  It's just a matter for my own knowledge of curious nerd. If you, say, have a cluster that contains a string, a Boolean value, and a digital control, a common method to reference the controls in the cluster is to create a cluster of reference and then to get the array of control from a property node. So let's say I wanted to put the Boolean value true, you can auto control array index and cast in more specific class boolean and set value via the property node (see below).

  

  Now my question is, to place controls of different types in a table must be returned by the property node, they must all be of the same class. How LabVIEW manages it? He cast as a more generic class backstage? If so, how this work because it is generally dangerous to come back from a class derived from a base class because the data can or will be lost.

  Furthermore, a standard molded type takes just a binary model and interperates as differently it based on the data type. So how is "of a more specific class" able to raise an error if a generic control reference cannot be transformed into a class more specific. For example, in the attached photo, a control string reference would be mistake out there, but how? They are all classes of generic control when they get out of the property node. Is there some type of indicator in the generic control reference indicating the type? Maybe I think about this fundemtally wrong. All I can think is that the more specific / are more generic vi no type casting (which I guess they are not because it has separate type cast feature).

  Can someone explain how this all works. Inquiring minds want to know.

  for (imstuck) wrote:

  Now my question is, to place controls of different types in a table must be returned by the property node, they must all be of the same class. How LabVIEW manages it? He cast as a more generic class backstage? If so, how this work because it is generally dangerous to come back from a class derived from a base class because the data can or will be lost.

  Furthermore, a standard molded type takes just a binary model and interperates as differently it based on the data type. So how is "of a more specific class" able to raise an error if a generic control reference cannot be transformed into a class more specific. For example, in the attached photo, a control string reference would be mistake out there, but how? They are all classes of generic control when they get out of the property node. Is there some type of indicator in the generic control reference indicating the type? Maybe I think about this fundemtally wrong. All I can think is that the more specific / are more generic vi no type casting (which I guess they are not because it has separate type cast feature).

  Can someone explain how this all works. Inquiring minds want to know.

  I don't know all the details, but I would say you got it mostly right - there is an implicit conversion to a more generic type.  You will see this in several places in LabVIEW, for example, you can wire references to different types of controls in "table to build" to get a picture of their more specific common parent.  Because you're only casting reference - not the data that it contains, there is no loss of data.  A LabVIEW reference is just an I32 is (I assume) an index into a lookup table somewhere.  The value of this I32 does not change when it is converted into a more generic reference.  When you do "to more specific Type", LabVIEW raises this reference in the table and uses the data it found to determine if she can make the cast.  Who help me?

• Comparison of matrix FPGA by element wierdness

  I have an application where I am comparing limits to the input values of two strain (OR-9237) inside an FPGA cards making a conditioning of signals for a subsystem in a larger machine.

  Process boundaries are sent to RT as a table and compared to a table of "raw" data entry

  Data entry-

  

  Comparison of limit-

  

  I do one per element to the "GOLDEN table" and I realize that this may or may not be more effiecient as a comparison aggregates; However, the strange thing that happens is that the sixth element of the array to limit triggers a "load error" for the fifth element of the input array.

  I send you the limit directly from the RT - PS

  

  Note that the verified calculation by reading the value defined in the FPGA. This set and get here seem to line up. That is to say, if you set the element 3 MaxLoad % or LCNominal(mV/V), it is validated on the FPGAMaxLoad output. I wonder if this has anything to do with the implicit conversion between floating-point single point-to-point fixed?

  If someone has had this experience, I would be grateful feedback on what is happening.

  I really want to engage in the DMA channel as it is a very small set of six elements that one, it seems more kill to use a DMA channel just for this operation.

  Thank you

  Drew

  
  

• Clipboard - Insert Utf8/Unicode characters to the Clipboard

  I wonder how to add support for unicode to the Clipboard method? Because when am copy my app textarea text, he turns to? (Arabic letters).

  Here are my codes which are related only to the Clipboard (added to these files):

  . Pro

  LIBS += -lbbsystem
  

  all

      Q_INVOKABLE
          void CopyText(QByteArray text);
  

  .cpp

  #include 
  #include 
  
  using namespace bb::system;
  
  qml->setContextProperty("_app", this);     void ApplicationUI::CopyText(QByteArray text)
  {
           bb::system::Clipboard clipboard;
           clipboard.clear();
           clipboard.insert("text/plain", text);
           bb::system::SystemToast *toast = new SystemToast(this);
           toast->setBody("Copied!");
           toast->show();
  }
  

  The function is called. QML

  import bb.system 1.0
  
                  ActionItem {
                      title: qsTr("Copy Text")
                      onTriggered: {
                          _app.CopyText(txtf1.text)
                                  }
                      imageSource: "asset:///images/ic_copy.png"
                  }
  

  I read a lot of forum messages and all API Tunis and I lost! as the use of tr() or QString::toUtf8 etc... !

  How can I solve this?

  Hello

  Please try changing the QString type parameter:

  void ApplicationUI::CopyText(const QString &text)
  

  In the function convert the text to UTF-8 byte array:

  void Application::CopyText(const QString &text)
  {
      bb::system::Clipboard clipboard;
      clipboard.clear();
      clipboard.insert("text/plain", text.toUtf8());
  
      bb::system::SystemToast *toast = new SystemToast(this);
      toast->setBody("Copied!");
      toast->show();
  }
  

  I think it was not working before because the function was already taking a QByteArray and implicit conversion (default) converted the ASCII instead of UTF8 encoding string.

  BTW, in function of the names Qt applications usually start lowercase letters, but this should not affect anything.

• A simple join

  Hello

  Is someone can you please tell me if I can use the concatenation of (|) operator to check as below Query2 NULL values? It will enhance any show in the course of using many '' AND '' conditions as below Query1?

  In addition, I check for NULL values on which different data such as Varchar, Date and number, if you concatenation operator to do the work?

  Instead of using "AND" a lot of conditions, is there a better technique to check if all the columns below are NULLs?

  Query1

  SELECT X.ENAME, Y.DNAME

  TABLE1, TABLE2 X Y

  WHERE X.ID = Y.ID

  AND X.COMM IS NULL

  AND Y.MGR IS NULL

  AND X.END_DATE IS NULL

  AND Y.DNUM IS NULL

  Query2

  SELECT X.ENAME, Y.DNAME

  TABLE1, TABLE2 X Y

  WHERE X.ID = Y.ID

  AND X.COMM: Y.Mgr: X.END_DATE: Y.DNUM is null

  
  

  Thanks in advance!

  VAMSi.
  

  Maybe (trying to avoid the implicit conversions)

  SELECT X.ENAME, Y.DNAME

  TABLE 1 X,

  TABLE2 Y

  WHERE X.ID = Y.ID

  AND coalesce (to_char (X.COMM),

  TO_CHAR (Y.Mgr),

  TO_CHAR (X.END_DATE, 'yyyymmdd'),

  TO_CHAR (Y.dnum)

  ) IS NULL

  
  

  Concerning

  Etbin

• display zero

  Hi how to display the number with zero no significant

  for example the number in the database is 10999222 and display it as 010999222

  I use lpad (empno, 1, 0) display 01:00 I have the 11 g database

  If you're talking about leading 0 on a number then the situation would be generally a requirement for a certain number of digits for example "the number should display with 9 digits, including zeros"

  In which case you use TO_CHAR function with a format mask, for example

  TO_CHAR (10999222, 'fm099999999')

  where the initial 0 in the format mask indicates 0 and the whole mask of 9 digits.

  Concatenation of '0' at the beginning wouldn't be a constant number of digits.  LPAD (10999222,9, '0') would be, but is not recommended because there is an implicit conversion from char to the first parameter number... and then you could do... LPAD (to_char (10999222), 9, '0') to prevent the implicit conversion, it's more work doing the TO_CHAR with a format mask.  TO_CHAR using with the format mask indicates clearly what you are trying to reach in the code for anyone to another reading too.