2,827 Posted Topics
 | [QUOTE=sonygamer;536272]I'm trying to use the switch function to compute the resistance of resistors. Basically, a person types in 3 letters, each representing a color; each color has a different value. Then v throws back the resistance by going through the equation. This is what I have so far. [code=c++] #include …  |
 | You should start a new thread. This one's a year and a half old. Also, remember the "Keep it on the site" rule. Post your question and have people comment on it in a public thread rather than e-mail your private e-mail address. |
| | I imagine you'll be using the mod operator ( % ) in your "if" statement. As in, given an integer m and a smaller integer n, if m % n is 0, then n is a factor of m. In C++, that would be something like this: [code=C++] if (m … |
| | You have two separate pieces of code. Which one are you asking about? This one? [code] a = (a + b) % 2; b = b – a; a = a * b; [/code] or this one? [code] a = a + b; b = a – b; a = … |
 | I experimented with your code and I think a problem might be that you are declaring, but possibly not setting aside memory for [code] float* planA; float* planB; [/code] When I put these two lines at the top of the function: [code=C++] planA = new float; planB = new float; … |
 | I imagine it is this line that is giving you trouble: [code=C++] infile.open("C:\Users\***\Desktop\School\chapter5.txt"); [/code] It's looking for a directory called "***" under C:\Users, which I imagine does not exist. I would replace *** with the user's name. Or it is possibly seeing the backslash as an escape character? Maybe try … |
| | What are the contents of the txt.txt file?  |
| | Re: help on string How about if you create a function that takes a large string (i.e. the user inputted sentence string named "line") and returns a vector of smaller strings? Each string in the vector would be a word. Something like this: [code=C++] vector <string> ParseIntoWords (string sentence); [/code] So in your example, …  |
| | This line here has an error in it: [code=C++] while ((a.get_x() 0 || (p.get_y() < 0)) [/code] The first half of the OR condition is this: [code]a.get_x() 0[/code]. I assume you want a comparison operator before the 0 such as =, <, >, etc. You are also returning 1 instead …  |
| | You are never initializing variable pay_type_1, which is your while loop control variable, so its value is whatever happens to be there from the last time that address was used. If that value happens to be zero or negative, you will never go through that while loop. |
| | These lines (99 - 101) as well as others look illegal to me: [code=C++] temp.book1[a]->name = (book1+a)->name; temp.book1[a]->address = (book1+a)->address; temp.book1[a]->number = (book1+a)->number; [/code] temp is of type address_book. address_book has a data member called book1, whose type is "pointer to addBook". I do not understand what you are referring …  |
| | I think you have a decent start. There are links on this site that discuss some of the potential perils of using the loop control style that you used (using "eof") that you may want to look at. [code=C++] while(!inFile.eof()) { } [/code] Here is one of them. There are … |
 | Re: exam It's a little easier to read when you put it in C++ format with C++ code tags since a lot of lines overflow. Put "code=C++" in the first bracket rather than just "code" and it gives the line numbers and makes the comments green. I'm not sure what you are … |
| | I got the same messages as you did when I tried to compile. It compiled and ran for me when I took the "char c" declaration outside of the while loop, like this: [code=C++] char c; while((c = cin.get()) != 'q') [/code] Possible the problem is that when c is … |
| | How about setting up a counter, initialize the counter to 0, then using a while loop? Each pass through the while loop could calculate the integer mod 10. If that result is 2 (or whatever digit you're counting), increment the counter. If not, don't increment the counter. Regardless, divide the … |
| | How about changing the function to take three arguments? In addition to the two arguments you already have (pointer to the beginning of the array and the size of the array), include a third argument: firstElementNotTested. The original call would have firstElementNotTested equal to 0, since no elements would have … |
| | There is nothing wrong with the original input loop. These are words/strings that the user is inputting, not integers or something like that, where a nested input loop would be required. If the array is supposed to be 20 x 20 like you mentioned in your example, you don't need … |
| | I believe possibly that the problem is in this line: [code=C] while (difference >= (1 * (10 ^ -4))); [/code] The carrot operator (^) here is interpreted not as raising 10 to the -4 power. Rather it is interpreted as doing a bitwise XOR on the numbers 10 and -4. …  |
| | Re: compile error Lemme see if I understand this. You have a program in a .cpp file and you want to create the .exe file from it? You obviously can't run/debug a project until you've built/compiled your project. You may have already tried this but have you clicked on the "Build Solution" option … |
| | Flipping the bits and adding 1 has to do with the 2's complement representation of integers. +174792 is this in 32 bit hexadecimal: 00 02 AA C8 You want negative -17492 so flipping the bits yields this: FF FD 55 37 In 2's complement, after you flip the bits you … |
 | You only have one data member in the Car class, right? That variable is called "RaceCarStatus" and it is a boolean type? RaceCarStatus is true if it is a race car and false otherwise, correct? As far as I can tell there is no data member called "i". You use … |
| | It looks like you are using the assignment operator (=) in the if statements rather than the comparison for equality operator (==): [code] if (Assignment = A) [/code] Also it appears that you are treating charaters as integers: [code] if (Assignment = A) [/code] rather than [code] if (Assignment == … |
| | Worked for me too. For the heck of it, maybe change: [code] double taxes = 0; [/code] to [code] double taxes = 0.0; [/code] Worked fine for me with the former, but the latter is probably better. Also see this for "void main ()". [url]http://www.daniweb.com/forums/thread61091.html[/url] |
| | [QUOTE=chandra.rajat;527102]Inside the Inner Loop [CODE]for (i=0; i < 3; i++){ for (j = 0; j < 3; j++) { inFile >> matrix[i][j]; printf("\n%f\t%f\t%f", matrix[i][j]); } }[/CODE] like this..[/QUOTE] You changed the printf line from the original Andy. Above is chandra.rajat's revised code based on your revised code. Here was your … |
| | You already have getDepartment and getSalary accessor functions. Write accessor functions getLastName and getFirstName. They'll be almost identical to getDepartment. [code] class Employee { private: char firstName[11]; char lastName[16]; char department[16]; double salary; public: Employee(); char *getDepartment(); char* getLastName (); // add this function. char* getFirstName (); // add this …  |
| | Yes that is the problem. Try replacing "%d" with "%f". "%d" expects an integer. Also, 6 is not a float. Might want to change that to 6.0. |
| | It works. I don't see the line he suggested in your code, so I don't know where you put it. The only change I'd make to carnage's advice is to put that line BEFORE the first getline, not after. You almost certainly have something "left over" in your cin input … |
| | Re: Searching Well as far as I can tell you are using the variable x but never initializing it and never changing it so it's functioning more like a constant with unknown value. You are reading data into a[x], but making "if" statements having to do with a[0]. Perhaps x is equal … |
| | I'd go with the "if" statements. I like Ancient Dragon's solution and it's more efficient, but since it's new to you it may be a little confusing when you're reading it later. The "if" strategy is going to be clearer since it's familiar. Something like this: [code] if (matrix[i][3] == … |
| | [code] case 1: printf("Choose a column"); scanf("%c",&s); {int v; for(v=0;v<20;v++) if(s[v]='A'||s[v]='B'||s[v]='C'||s[v]='D') s[v]='*'} printf("%s",s)break; case 2: printf("Choose a column"); scanf("%c",&s); int v; for(v=0;v<20;v++) if(s[v]='A'||s[v]='B'||s[v]='C'||s[v]='D') s[v]='*'} printf("%s",s) break; case 3: printf("Choose a column"); scanf("%c",&s); int v; for(v=0;v<20;v++) if(s[v]='A'||s[v]='B'||s[v]='C'||s[v]='D') s[v]='*'} printf("%s",s) break; case 4: printf("Choose a column"); scanf("%c",&s); int v; for(v=0;v<20;v++) if(s[v]='A'||s[v]='B'||s[v]='C'||s[v]='D') s[v]='*'} … |
| | You're adding up to one more than the number of times through the loop because you are initializing heads, which is the number of times you get a heads, to 1 rather than 0 in the beginning with this line: [code] heads = 1; [/code] You are comparing "toss", the … |
 | There is the vector class. There's also a queue and/or a linked list. All of those can expand and shrink as needed. [url]http://www.cplusplus.com/reference/stl/vector/[/url] [url]http://www.cplusplus.com/reference/stl/queue/[/url] [url]http://www.cplusplus.com/reference/stl/deque/[/url] |
| | [QUOTE=woozy;523953]Say I have an infinite loop, and I want to start over or terminate depending on what user inputs. [CODE] while( 1 ) // start the inifite loop { printf( "Enter your number: " ); // prompt scanf( "%d", &operand1 ); // store user entered number into operand1 if ( …  |
| | english1 and english2 don't appear to be initialized. Also, in this line: [code] while((answer != english1) || (answer != english2)) [/code] you are comparing answer to the [U][B]addresses[/B][/U], not the [B][U]contents[/U][/B] of the variables english1 and english2. String comparisons don't work the way integer comparisons do. Instead of using == …  |
| | I replaced the commas in line 34 with plus signs and it seemed to work: [code] decimal_value= value_1 + value_2 + value_3 + value_4,value_5,value_6,value_7; [/code] |
| | There is no pow (int, int) function. You have to write your own. [url]http://www.cplusplus.com/reference/clibrary/cmath/pow.html[/url] As for the printf warning, I don't see that in your code, so I can't comment. |
| | Hmm. I thought I had posted a few minutes ago, but I don't see it. I'll post again. You have a mix of doubles and integers, so the 2-D array from the last problem will no longer do the job. I'd create a struct of three integers and two doubles … |
| | I think your algorithm has some problems. In this line: [code] while(n != 0) [/code] you are already deciding how many times you are going through the loop. n has been passed to div. So if n was 5, you're going to go through the loop 5 times? Not true. … |
| | Re: Trapezium Rule [code=C++] double trap (int n, double a, double b) //Function 2 Calculation of the areas of the strips, called trap { double d, h=0, area; d=(b-a)/n; //d=Strip Width, "a" and "b" are the upper and lower bounds of the integral for (int i=1; i<=(n-1); i++) // changed commas to semicolons … |
| | Not sure if this defeats the purpose of your program (it's not recursive), but for a problem with numbers as small as this, where everything is natural numbers and less than 100, you could change the equation to: y = 100 - 3x - 4xz and do a brute force … |
| | He added those compile tags to list the warnings. Without them it compiles, but doesn't list them. He has a good point about "abt", "tat", etc. when he listed the link. It's hard to take your question seriously when you write like that.  |
| | [QUOTE=mark192;522008]also say i wanted to list several numbers in one if statement how would i do that? [code]If (x != 1, 2, 3, 4)[/code] Doesn't seem to be working[/QUOTE] && means "and". || means "or". Try this: [code] if (x != 1 && x != 2 && x != 3 … |
| | Re: Program help [QUOTE=coolbreeze;521013] [code] int n, sum; int total=0; [/code] [/QUOTE] Make sure you initialize the variable sum to 0 here too because you are using it later here without initializing it: [QUOTE=coolbreeze;521013] [code] sum += i; [/code] [/QUOTE] You want to use && for "AND", not a semicolon below: [QUOTE=coolbreeze;521013] [code] … |
 | You can change your getline in the second program to this: [code] getline(myfile, msg, '\n'); [/code] I'm assuming you want the whole line of input till the newline character? Wasn't sure what the 40 represented so I ignored it. |
| | [QUOTE=chandra.rajat;519576][CODE] char line1; int line2a, line2b; char val1[4],val2[4]; char delim = ' '; indata>>line1; cout << " The ASCII value of your character is " << (char)line1 << endl; ; indata.getline(val1,4,delim); line2a = atoi(val1); indata.getline(val2,4,delim); line2b = atoi(val2); [/CODE] [/QUOTE] You're making this way too complicated. Just do this: [code] … |
| | You have "name" declared as a char, so it can only hold one character. You can change name to a string or a char* and it'll be able to hold more. |
| | Well when you are inside this loop, [code=C++] while(!realEstate.eof()){ cout << "I am here!3" << endl; //just used for debugging if(!RecordToRead.deleted){ //if file is not deleted, procede numberOfClients++; feeTemp =(RecordToRead.agentFee * RecordToRead.purchasePrice); feeTotal = feeTotal + feeTemp; } } [/code] you are not ever reading anything from the fstream "realEstate". … |
| | I think just replace this: [code=C++] for(int i=0; i<20; i++) { cin>>fileName[i] if(fileName[i]=='\n'; { break; } } [/code] with this: [code=C++] cin.getline (fileName, 20, '\n'); [/code] |
| | [QUOTE=george45;520216] Output from my program 0) 0.162537 1) -0.0823975 <--Value out of range of [0.5, -0.5] 2) 0.0454712 <--Value out of range of [0.5, -0.5] 3) 0.226471 4) 0.258606 5) 0.129608 6) 0.035675 <--Value out of range of [0.5, -0.5] 7) -0.00393677 <--Value out of range of [0.5, -0.5] 8) … |
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