C++ :: How To Get The Value Of Variable From Equation

Mar 25, 2013

how to take two variables with values such as a 1; and b 2;. Now you take cout << a + b; and you will get 3, but I want to somehow have a 1; b 2; and c num; then have a + b = c. So what ever I have the user input is for a and be added together will become the value of the c variable.

View 1 Replies


ADVERTISEMENT

C :: Quadratic Equation - ID Returned 1

Oct 18, 2013

This is my code:

Code:
#include <math.h>
#include <stdio.h>
int main(void) {
float a,b,c,root_1,root_2;
printf("Please enter value a from the quadratic equation

[Code] ......

And I keep getting this error:

Code:
/tmp/ccgtUIun.o: In function `main':
assign345.c:(.text+0xc7): undefined reference to `sqrt'
assign345.c:(.text+0xef): undefined reference to `sqrt'
collect2: ld returned 1 exit status

View 5 Replies View Related

C :: How To Get Values From The User And Add Them To Equation

Oct 30, 2014

I have a small project for school due today but i cant get my head around programming

Ive to create a program where ive to get the values from the user and add them to an equation. I have also to add a selection statement where it will ask for the material being tested which will have its value set in the program.

View 4 Replies View Related

C++ :: Distance Between 2 Points Equation

Apr 14, 2013

Write a program that creates the output shown in the Output Layout section below. The program should create 2 points with x and y coordinates as integers, prompt the user to input the x and y values for one of the points and randomly set the other (-99 to 99 range) and output the length of the radius line segment and the area of the circle that radius defines. The program should then end. Include an SDM for the program and any other appropriate documentation.

Special Calculations:
Distance between 2 points equation:
√((p0x – p1x)2 + (p0y – p1y)2) (This requires use of the math library)

Output Layout: (bold text represents user input)

Please enter the location of your first point.
Enter a value from -99 to 99 for your x coordinate: -2
Enter a value from -99 to 99 for your y coordinate: 17

The location of your second randomly set point.
Your x coordinate: 45
Your y coordinate: -89

The length of the radius line segment from point one to point two is 115.
The area of the circle with a radius of 115 is 41546.33.

Other:

int pAx;
int pAy;
int pBx;
int pBy;

View 3 Replies View Related

C++ :: Quadratic Equation - Output Is NAN

Jul 4, 2014

soo quadratic equation solver. output is "x=nan x=nan".

#include <iostream>
#include <string>
#include <cmath>
using namespace std;
//prototyping
double ans_1(double,double,double)

[code].....

View 2 Replies View Related

C/C++ :: Optimizing Equation For Cases Of 0

Feb 19, 2015

I'm writing an algorithm on a microcontroller in C.

One of the iterations that takes a long time involves the following equation, summing the product of pairs of variables:

signed char VarA;
signed char VarA;
signed long VarA;
Total+=VarA*VarB;

The vast majority of cases, at least one of the variables VarA and VarB will be 0, so nothing will be added to Total.

Is there a way to check for this condition which might give me a performance increase over doing a lot of multiplying-by-zeros?

View 6 Replies View Related

C :: Program To Solve The Quadratic Equation

Feb 3, 2013

I am creating a program that solves the quadratic equation ax^2 + bx +c.

I have this program almost complete except the output of the equation in the function called display_quadratic. I need the program to display the variables a,b,c in the equation ax^2 + bx + c but I am having 2 problems. My first problem is that I cannot get the right addition and subtraction signs for the equation.

For instance, if the program had the values for a,b,c as 2,2,3

it will display 2x^2 2x 3

How can I get it to display 2x^2 + 2x + 3? or if it was negative like 2x^2 - 2x - 3?

My next question is how do I get to not display the coefficients that are 1?

I had an if-else statement but no matter what I created it would overlap with another statement and print out twice. Here is the code:

Code:
#include <stdio.h>
#include <stdlib.h>
#include <math.h>

void display_quadratic (float a, float b, float c);
float root1(float a, float b, float c);

[Code] ......

View 2 Replies View Related

C :: Multiple Roots For Quartic Equation

Sep 10, 2013

I am having trouble understanding how this loops would work. Give the function (x*x*x*x) - (10*x*x*x) + (35*x*x) - (50*x) + 24 Write a program that will use bisection method to find the roots of this function. Define lower limit and upper limit (e.g. -1.05 and 6.05) Starting at the lower limit step along the X axis at intervals of 0.1 for H calculating the function values f(x) and f(x +h), then f(x+h) and f(x+2h) until the upper limit is exceeded. If sign of the function value changes this indicates a root between ranges. Apply bi sectional method to this range until root has been found with an epsilon of 0.000001, then continue on until upper limit has been exceeded and all 4 roots found. If the function is within 0.000001 of zero then root has been found therefore no need for bi sectional method.

Code:

#include "stdafx.h"
#include "math.h"
#define H 0.1
#define epsilon 0.000001
double F(double x);
int main(void)

[code]....

So we have a function and a range. Program requires to work along the X axis at 0.1 increments until it reaches a point where the value changes from positive to negative or negative to positive. Then apply bisection method within that range to a given accuracy then print that root. Then continue on X axis until the next change of sign is found.

View 8 Replies View Related

C++ :: Calculating Equation Using Expression Builder

Jan 22, 2014

How do to calculate the following equation"5+((56+8)/2)" using expression builder

Note: the equation may change "50+((26+8)/12)"

View 1 Replies View Related

C++ :: Trapezoidal Method Differential Equation

May 11, 2013

I am working on a program to find the value of the current in a coil. This value satisfies the following equation:

y'=sin(2t)-[(ey-1)/(ey+1)]

which is of the form y'=f(t,y)

I know that in order to solve this I need to use the trapezoidal method to solve a differential equation, the formula is:

yn+1=yn+.5*h(f(tn,yn)+f(tn+1,yn+1) where h=tn+1-tn

I have found examples of the standard trapezoidal method but I do not think they will work because of the difference in the formulas.

View 2 Replies View Related

C++ :: Quadratic Equation - No Matching If Statement

Oct 7, 2013

This is my code for the quadratic equation. It keeps telling me that my else is illegal since no matching if statement and my else statement is missing a statement

#include <iostream>
#include <cmath>
#include <string>
#include <iomanip>
using namespace std;
int main() {
string Name;

[Code] .....

View 3 Replies View Related

C++ :: Program Returning NaN For Quadric Equation

Mar 29, 2013

My program is returning NaN even though the value in square root function is not negative -1*b + ((sqrt(pow(b,2) * -4 *(a*c))) / 2).

x = 10;
y = -1;
z = 1;

Heres the program:

main.cpp:

#include <iostream>
#include "Quad.h"
double x,y,z; // variable x = 'a', variable y = 'b' and variable z = 'c'.

[Code] ....

I would like it return the answer and not "NaN".

View 10 Replies View Related

C++ :: Allowing For User Input Of Equation To Be Evaluated

May 14, 2014

I've written a program that finds the maximum of a function. I now want to change it a little so that instead of evaluating the function y=x^2-7x-18, the program will ask the user to input an equation and then evaluate that equation. I'm really not sure of how to do so.

#include <iostream>
#include <cmath>
#include <cstdlib>
using namespace std;
int main() {
int a, b, delta, x, y;
double max= -1.8 * pow(10, 308);

[Code] .....

View 3 Replies View Related

C++ :: Enter Equation All At Once Instead Of Prompting For Each Piece Separately?

Mar 4, 2014

How do I enter the equation all at once instead of prompting for each piece separately?

#include <iostream>
using std::cin;
using std::cout;
using std::endl;

[Code].....

View 4 Replies View Related

C++ :: Finding The Root Of Equation Using Secant Method

Feb 8, 2014

I want to find the root of an equation f(x) by using the secant method [URL] .....

#include <math.h>
#include <iostream>
using namespace std;
//Define function f(x)
double f(double x, double a, double b) {
return sin((a*x)/(1+x*x))*atan(b*x)+atan(x);

[Code] ....

1) Do I have to keep the function f and RootFinderSMNew in different cpp files?

2) When compiling I get the following errors:

1>------ Build started: Project: Assignment2.1, Configuration: Debug Win32 ------
1> Find Roots Secant method.cpp

[Code] .....

What am I doing wrong ?

View 1 Replies View Related

C/C++ :: Quadratic Equation Solver - Simplification Function

Jul 6, 2014

So, I successfully made a program that will perform the quadratic equation on three numbers, imaginary or real. however, i am now trying to simplify the result, as to get rid of the "/2a" on the bottom. Hence the simplify() function. I just started to create the simplification function, and am attempting to divide the imaginary part of the solution as well as the real part of the solution by 2a. Somehow, it gives the error, "error:invalid operands of types 'int' and 'double *' to binary 'operator*'" on lines 105 and 106. I suspect it has to do with the pointers and references that i am passing as parameters. Also, just an aside, I have never actually seen "/=" be used. It can be, right? I know "+=" can be.

#include <iostream>
#include <string>
#include <cmath>
#include <cstdlib>//simplify the answer
using namespace std;
int count=0;
//prototyping
double ans_1(double,double,double);

[Code] ....

View 5 Replies View Related

Visual C++ :: Arrays - Solve Equation Using All Volume Values

Dec 22, 2012

I am using matlab R2o11 in which the programming medium is c++. I am having these variables=

T=373 t0 376
V=0.09 to 1
P=T/V

I just need a result showing ... First it should take T=373 and solve the equation using all volume values. Then it takes another temperature and do the same.

View 4 Replies View Related

C++ :: Equation That Determines The Lowest Possible Cost For Laying Power Line

Apr 9, 2013

I need an equation that determines the lowest possible cost for laying power line.

The variables are as follows:

1. The width of a river
2. The distance a factory is downstream from a station on the other side of the river.
3. The cost for laying line underwater.
4. The cost for laying line on land.

All these variables will be user input each use of program.

View 4 Replies View Related

C++ :: Type Conversion - Float Or Double Variable Into Unsigned Char Variable And Back

May 10, 2013

I would like to convert a float or double variable into unsigned char variable and back.

float number_float = 23.453f;
unsigned char* number_char = (unsigned char*)malloc(sizeof(float));
number_char = reinterpret_cast<unsigned char*> (&number_float);
float* number_float_0 = reinterpret_cast<float*>(&number_char);

I am not getting the same value back.. why?

View 2 Replies View Related

C++ :: Store A Reference Variable As Member Variable Of Interface Object

May 1, 2013

I am having trouble compiling my interface. I am trying to store a reference variable as a member variable of the interface object. Compiler says that the variable has not be initiated correctly.

LCD inherits from VisualInterface which is expecting a DisplayDriver object to be passed in (DisplayDriver is another interface, but thats not important).

I pass the displayDriver object in when LCD is instantiated in maininterfaces.zip

I was pasing it before as a pointer but was told that this could cause me problems with memory leaks and a reference was better, but now I cant seem to get it to compile.

View 11 Replies View Related

C++ :: Storing Variable Size Pointers Array As Class Variable

Mar 2, 2013

This problem is best explained by looking at its output below. I stored 15 different values but when retrieved some are wrong.

#include <iostream>
using namespace std;
class A {
public:
int ** pointer;

[Code] ....

I need to store and retrieve the 15 different values correctly. How to solve this? The main thing is, I need to store the pointer in class A objects.

View 6 Replies View Related

C++ :: Write A Loop Assigning Variable X To All Positions Of String Variable

Sep 8, 2013

I have to write a loop assigning a variable x to all positions of a string variable and I'm stuck. I don't have extensive experience with arrays and I'm also a bit confused about C-String. The problem is below.

"Given the following declaration and initialization of the string variable, write a loop to assign 'X' to all positions of this string variable, keeping the length the same.

char our_string[15] = "Hi there!";

(Please note this is a 'C-string', not C++ standard string.)"

View 5 Replies View Related

C :: Transform Local Variable Into Global Variable?

Oct 25, 2014

I need to transform a local variable into a global variable so I can use it in one of my functions. I thought about passing the value as a parameter to this function but I can do this since the function is called inside the while loop and this variable counts how many times the while loop does (so the final value is outside the loop). Example to visualize better:

Code:
while(condition) {
function(parameter1, parameter2);
count = count + 1;
}
printf("%d
", count);

So, I need to transform the final value of "count" into a global variable. Can I do this?

View 5 Replies View Related

C++ :: Store Function To A Variable And Call It Using That Variable?

Oct 15, 2013

I want to store few different functions to a variable for different structs/classes and then call it later using that variable, is it possible? something like

struct item {
int ID;
int special; // for function
};

item Key;
Key.special = UseKey(KEY_KING);

// now when I want to call function "UseKey(KEY_KING)" I want to use "Key.special", like this

if(iCurrRoom == ROOM_KING)
Key.special;
else if(iCurrRoom == ROOM_DRAGON)
Fireball.special;

View 5 Replies View Related

C/C++ :: Assign One Variable Address To Another Variable

Feb 3, 2014

I've been experimenting with pointers and am getting the below error.

'error: cannot convert 'int**' to 'int*' in assignment'

I thought it was ok to assign a variable address to another variable. Line 18 is where I get the error.

I am trying to show the progression of memory as I increment it as I have done on line 17 and again, I don't know why I don't see a progression through memory locations when output to the console on line 20.

Here's the code:
#include <iostream>
#include <cstring>
#include <cstdlib>
using namespace std;
int main() {

int *tt = new int;
int *p = new int;

[Code] .....

View 6 Replies View Related

Visual C++ :: Creating A Variable Using A Variable?

Jun 16, 2013

Any way to create a variable using a variable in the name? So E.g. if you wanted to create an int named nr(x), and x was 1, you would get an int variable named nr1? How would you do this?

View 10 Replies View Related







Copyrights 2005-15 www.BigResource.com, All rights reserved