What is the meaning of $d$?
Difference between $\Delta$, $d$ and $\delta$
I need to test this code, but when writing a trigger, I get an invalid type I need help. I am currently trying to test this code before uploading  public class CoreValuesExt { ApexPages.StandardController sc; public boolean readonly {get; set;} public Core_Values__c cv {get; set;} public integer countEdit = 1; public string buttonValue {get; set;} public integer recordScan;  public CoreValuesExt(ApexPages.StandardController sc) {     this.sc = sc;     cv = new Core_Values__c();     cv.Account__c = sc.getid();      readonly = true;     buttonValue = 'Edit';     recordScan = [SELECT COUNT() FROM Core_Values__c WHERE Account__c = :cv.Account__c];    if (recordScan != 0){    cv = [SELECT id, HSE__c, Professionalism_Integrity__c, Quality_Accuracy__c, Technology_Innovation__c, Timeliness__c, Value_for_money__c FROM Core_Values__c WHERE Account__c = :cv.Account__c];     }  }  public ApexPages.PageReference Save() {     return sc.Save(); }  public void ApplyAction() {     countEdit++;     Integer modolus = Math.mod(countEdit, 2);     String total = cv.HSE__c + cv.Professionalism_Integrity__c + cv.Quality_Accuracy__c + cv.Technology_Innovation__c + cv.Value_for_Money__c + cv.Timeliness__c;     if(modolus == 0)     {         readonly = false;         buttonValue = 'Save';     }     else     {         if(total != 'nullnullnullnullnullnull')            {         if (recordScan == 0){         insert cv;         readonly = true;         buttonValue = 'Edit';         }         else         {         update cv;         readonly = true;         buttonValue = 'Edit';         }         }     }    }   }  With this trigger.  trigger CoreValuesTrigger on Core_Values__c (before insert) {  Core_Values__c cvs = Trigger.new; CoreValuesExt.ApplyAction(cvs);  }   But when I try to save, I get a message saying:      Illegal assignment from List to   CoreValuesExt__Core_Values__c at line 3 column 1   "  How do I go through with this? I need help. Thanks From Windows Vista to 7, can I get rid of folder Windows.old? I've just changed my laptop OS from Windows Vista to Windows 7.  I didn't choose to have both OS together, I just want to have Windows 7.   I was specting Windows 7 instalation program to format/clean my HD and leave me most of its capacity for a fresh start. But I've found, once the OS has been isntalled, that all files and programs from the Vista era are still in my HD, in a folder called Windows.old   I don't need these programs and files, I want to have as much HD space as possible and Windows 7 as clean as possible, what should I do?  Can I just delete Windows.old folder? Would that affect the how Windows 7 works?  Maybe is because I ended up angry with Vista, but I don't like the fact that there wasn't any cleaning/formatting ..   Thanks a lot Suppose that:  $0 \rightarrow M_{1} \rightarrow M \rightarrow M_{2} \rightarrow 0$  Is an exact sequence of $R$-modules (for $R$ commutative integral domain). Show that $\mathrm{rk}(M) = \mathrm{rk}(M_{1})+\mathrm{rk}(M_{2})$    I have shown the inequality $\mathrm{rk}(M) \geq \mathrm{rk}(M_{1})+\mathrm{rk}(M_{2})$, however for the opposite direction I'm lost. I tried to take $N$ as a linear independent subset and tried to decompose it into $N_{1}$ (the elements in $\mathrm{Ker}(g)$) and $N_{2}$ (the elements not in $\mathrm{Ker}(g)$), but I haven't got far, since $N_{1}$ gives us a linearly independent set in $M_{1}$, however $N_{2}$ can give us a linearly dependent set in $M_{2}$.   We define $\mathrm{rk}(M)$ in this case as the supremum over all cardinalities of the linearly independent subsets of $M$ (where the only finite linear combination equaling $0$ implies trivial coefficients for $r \in R$).  Would this be the proper way to show the result? I think I'm missing something important. Print lines between (and excluding) two patterns Boggle: What is the dice configuration for Boggle in various languages? This is the dice configuration for the English Boggle:  Other variants and discussions concerning letter distributions for English can be found here:  , , ,  (Wikipedia).  I am interested in the 16 dice configurations for also other languages (Spanish in particular) and I am unable to find it anywhere online.  Versions I have managed to find so far:  ,  English 25 dice version:   Spanish 25 dice version:   Italian 25 dice version: How to include time factor in a mixed model (investigating the interaction between two factors and time)? Using the definite article before a country/state name The Punjab is a rich state.   Is it correct to use the before Punjab? Error: the question could not be loaded When I was trying to open  I just added using the iOS app I received this error:     Error The question could not be loaded   Reproduction scenario:   add a question; in my case it didn't open it directly; it doesn't show up in the list yet; I opened my profile and clicked the question; bang! PHP function substr() error Greatest and Least Resistance and Current Characteristics of Parallel vs Series circuits Which type of circuit would have the greater resistance?  Which type would have the greater current? and Why?  My book says that parallel has the greater resistance than current as parallel wiring if thought as water pump tubes has greater resistance during water flow.  Contrary to my book, if I make up numbers to solve for which has the greater resistance, i find that  series has greater resistance.  Equivalent resistance of 2 Ohm resistor in series is greater than that of 2 resistors with 2 ohms in parallel. I Is there anything like GF(6)? Taylor series expansion for $f(x)=\sqrt{x}$ for $a=1$ How do you declare an interface in C++? How do I setup a class that represents an interface?  Is this just an abstract base class? How can I unlock my phone? I locked it using Android Device Manager, but it claims I entered a wrong password I have an Samsung Galaxy S3 Neo.  Bus 002 Device 042: ID 04e8:6860 Samsung Electronics Co., Ltd GT-I9100 Phone [Galaxy S II], GT-I9300 Phone [Galaxy S III], GT-P7500 [Galaxy Tab 10.1]   The keyboard &amp; language setting is português.  I today installed Android Device Manager and to test it's functionality I locked the phone with the password: "abcd" (4 letters were required).  After entering the password and confirming with the "OK" button of my keyboard, the phone showed me that the password is wrong. "Senha incorreta".  I reset the password after some tries to "123456" and the phone reloaded the lock screen. Again the password showed up to be wrong. I also tried the alphabetic password: "abcdefg" - same error.  I changed the language of my Google account from German to Portuguese and reset the password to "123456" again and I tried to really reboot my phone and unlock the SIM card again. But anyways I can not get through my lock of the Android Device Manager.  I tried to enter the password 35 times wrong with hope to get a chance to authenticate with my Google Account login.  I also tried to connect the phone with adb but it does not show up in this state with:  adb devices   So what can I do to get access to my phone again? How can I create a water material in Cycles? The new profile shouldn't mistakenly imply that you can earn the Informed badge on a meta site I just joined Sports, and I decided to take a look on Sports Meta. I clicked on my profile there. This is part of what I saw:     Yet the profile shouldn't indicate that it is, in theory. . .  This seems to be a bug. Limiting double to 3 decimal places I have a SQL Server 2005 database using the full recovery model. If I execute the following commands:  ALTER DATABASE test SET RECOVERY SIMPLE; ALTER DATABASE test SET RECOVERY FULL;   or   BACKUP LOG test WITH  truncate_only;   Then try to run a log backup:  BACKUP LOG test TO  DISK = 'backupfile.bak'   I receive the error message:     BACKUP LOG cannot be performed because there is no current database backup.   Question:     How do I check that I will not be able to take a log backup, without running a backup log command? root of an odd degree polynomial Im asked to prove that a polynomial of an odd degree has a root. Im going to use IVT to prove this, but I'm wondering if I can use the assumption that an odd degree polynomial has either two cases:  $$ \lim_{x\to\infty}h(x)=+\infty \\ \lim_{x\to-\infty}h(x)=-\infty \\ $$ $$and$$ $$ \lim_{x\to\infty}h(x)=-\infty \\ \lim_{x\to-\infty}h(x)=+\infty \\ $$ Then by this there exists numbers $a,b$ such that $$ h(a)&lt;0&lt;h(b) $$ $$or$$ $$ h(b)&lt;0&lt;h(a) $$ Which I think would prove that odd degreed $h(x)$ has at least a root. Or is there a more convincing way to show that there are numbers in $h(X)$ greater than zero and less than zero?  edit: (sorry about the bad limit notation) My images are blurry! Why isn't WPF's SnapsToDevicePixels working? I'm using some Images in my WPF applcation.  XAML:  &lt;Image Name="ImageOrderedList"        Source="images/OrderedList.png"        ToolTip="Ordered List"        Margin="0,0,5,5"        Width="20"        Height="20"        SnapsToDevicePixels="True"        MouseUp="Image_MouseUp"        MouseEnter="Image_MouseEnter"        MouseLeave="Image_MouseLeave" /&gt;   But, they appear fuzzy.  Why doesn't that SnapsToDevicePixels="True" line prevent this problem?